JPH03111162A - Method and device for generating work face of grinding tool - Google Patents

Abstract

PURPOSE:To avoid the fouling of a work environment by performing a series of works and stages from the shape generation of the grindstone face of a grinding tool for an optical lens, etc., to the so-called setting which makes it in a sharp state, in the same device. CONSTITUTION:A conductive grinding tool 1 and conductive reference tool 11 for generating the work face of this conductive grinding tool 1 are rotated and opposed, also the specific shape of the conductive reference tool 11 is generated with its transfer on the work face of the conductive grinding tool 1 by executing an electric discharging in an electric discharge machining liquid 28 while impressing an anode to the conductive grinding tool 1 and a cathode to the conductive reference tool 11 respectively. Then, the distance between the relative faces of the conductive grinding tool 1 and conductive reference tool 11 is held constant and the setting of the work face of the conductive grinding tool 1 is performed by using a DC current while feeding an electrolyte or a weak coolant 30 between this relative face.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention performs initial creation of the machined surface shape of a grinding tool for grinding hard and brittle materials such as glass and ceramics in combination with dressing of the grinding tool. This article relates to a method and device for creating a machined surface for a grinding tool.

[Prior Art] Generally, when grinding and polishing a workpiece, for example, an optical material (such as glass) into a spherical shape, it is customary to use a grinding or polishing tool such as a grindstone.

In the following, conventional processing techniques of this type will be explained using FIGS. 6 to 9, taking as an example spherical surface creation and grinding and polishing tools for optical lens processing.

FIG. 6 is a block diagram of the main parts of a processing device for grinding and polishing an optical lens using a grindstone.

In the figure, a grindstone 2 is constructed of a bullet-type tool, and is constructed by pasting a plurality of grindstones 2 to a tool 3 using an adhesive 4.

Thus, a grindstone 2, a tool 3 and an adhesive 4. The configuration is collectively called a grinding tool.

Further, the grinding tool 1 having the above configuration has the following features as shown in FIG.
There is also one in which a grindstone 2 having a predetermined machining spherical surface R and a tool 3 are integrally formed. The grindstone 2 is made of a sintered alloy which is a special mixture of abrasive grains such as diamond powder and metal powders such as Cu, Sn, and Kasa, and is heat-treated.

Now, the grinding tool 1 is rotatably held on the rotating shaft 10 by screwing the threaded part 3a provided on the tool 3 to the threaded part 10a of the rotating shaft 10, and the optical lens which is the member to be ground and polished. 5 is placed on the grinding tool I via a holding plate 6, and is pressed and held by a rod 7 connected to a swinging and pressing mechanism (not shown).

Then, the rotating shaft 10 is rotated by a drive means (not shown) to rotate the grinding tool 1, and the rod 7 is pressed, and the optical lens 5 is pressed and swung through the swinging mechanism. The processing surface of the optical lens 5 is ground and polished into a predetermined processing spherical surface R while discharging a grinding coolant 9 onto the grinding surface from a vibrator 8 connected to the supply section.

Now, after the initial manufacturing of the grinding tool l used for grinding and polishing the optical lens 5, creation of a predetermined processing spherical surface R and dressing of the grinding wheel 2 are performed, and then the grinding tool l used for grinding and polishing the optical lens 5, It is used for polishing.

Figures 8 and 9 show the grinding tool 1 after initial installation.
FIG. 3 is an explanatory diagram showing a method of creating a processed spherical surface R of a grindstone (buret) 2 and dressing (dressing) processing method in FIG.

As shown in Fig. 8, the grindstone (berlet) 2 has a machining slope R.
In order to achieve this, it is necessary to shave off the diagonal diagram B, and since there are irregularities on the surface A as shown in Figure 8, the approximate processed spherical surface after processing corresponding to the processed spherical surface R is After applying the processed whetstone 2 to the tool tool 3, as shown in FIG. By doing this, the unevenness of the shaded area B and the surface A shown in FIG. 8 is removed, and the surface of the grindstone 2 of the grinding tool 1 is sharpened (initial dressing).

The free abrasive grains 12 used in the machining are changed several times from one with a large grain size to one with a gradually smaller grain size, and the ramping process is performed. At the same time, the machining spherical surface R is corrected, and the axis center I or the axis shown in FIG. Wrap tool 1 at the mouth position
The work of moving the center of arrow C and changing the swing width of arrow C is mainly performed manually.

[Problems to be Solved by the Invention] However, there are the following problems in creating and sharpening the machined surface of the grinding tool.

That is, an enormous amount of time is required to create the grinding wheel surface of the grinding tool by lapping, and time for sharpening is required.

In addition, the creation of the grinding wheel surface of a grinding tool on a ramp tool pan by lapping through free abrasive grains, ) changes, and the shape of the lapping tool plate (
It is necessary to correct R) in Fig. 9. In other words, a part of the lapping tool plate is ground with hand-hyde or a solid whetstone, and the 9th
It is necessary to reduce or increase R in the figure.

Furthermore, sharpening from lapping via free abrasive grains (
(dressing), there is a considerable amount of diamond abrasive grains falling off the grinding wheel surface of the grinding tool, resulting in a tool with poor grinding ability and poor grinding efficiency in optical lens grinding work.
Dressing frequency also increases.

Moreover, work using such free abrasive grains poses problems such as contamination of the working environment.

The present invention was developed to solve the above-mentioned problems, and aims to provide a method and device that can perform processing creation and sharpening of grinding tools in a short time, with high precision, and without contaminating the working environment. That is.

[Means and effects for solving the problem] FIGS. 1 and 2 are conceptual diagrams of the present invention.

A holding device for rotatably and relatively movably holding the conductive grinding tool 1 and the conductive reference tool 11, which are constructed by pasting a plurality of pellet-shaped grindstones 2 on a tool tool 3 with an adhesive 4, is opposed to each other. A rotating shaft 22.23 rotatably attached to the upper and lower housings 20.21 and this rotating shaft 22.23.
The drawing tool is constituted by threaded parts 22a and 23a, which are provided at the tip of the conductive grinding tool 1 and threaded into the threaded part 11a of the conductive reference tool 11, respectively. A driving unit (not shown) in which rotating and relatively moving driving devices 1 and 11 move the rotating shaft drive motor 24.25 connected to the rotating shaft 22.23 and the upper housing 20 in the direction of the arrow in FIG. It is composed of.

Further, the drive device is equipped with a control section (not shown), and the arrows on the upper housing 20 required for machining work (see FIG. 1)
The motors 24 and 25 are controlled to move up and down in the directions, rotate the rotating shaft 2223, and stop the motors 24 and 25.

Further, a machining tank 26 for electrical discharge machining or sharpening of the conductive grinding tool 1 and the conductive reference tool 11 is disposed between the upper and lower housings 20.21, and the machining tank 26
An insertion portion 27 for the rotating shaft 23 is provided at the bottom of the rotary shaft 23 in a transparent manner.

The machining tank 26 has an electrical discharge machining fluid 28 in it.
A supply section 29 for supplying a liquid and a supply section 31 for supplying an electrolytic solution or a weakly electric coolant 30 are provided.

The electrical discharge machining fluid 28 in the supply unit 29 is supplied into the machining tank 26 via a supply pipe 34 by a pump P provided in the supply unit 29, and is also supplied through a discharge pipe 35 connected to a valve 32 provided in the machining tank 26. The electrolytic solution or weakly electric coolant 30 in the supply section 31 is supplied into the processing tank 26 via the supply pipe 36 by a pump P2 provided in the supply section 29. It is configured such that it can be collected into the supply section 31 via a discharge pipe 37 connected to a valve 33 provided in the processing tank 2G.

Further, a power supply section 40 of a DC power supply and an AC power supply that applies electrodes to the conductive grinding tool 1 and the conductive reference tool 11 is provided, and an anode from the power supply section 40 is electrically connected to the rotating shaft 23. The power is applied to the electrically conductive grinding tool 1 through a power supply brush 41 and to the conductive reference tool 11 through a power supply brush 42 whose cathode is electrically connected to the rotating shaft 22 .

Now, the conductive reference tool 11 held on the rotating shaft 22
The machined surface is precisely machined into a spherical surface with a machined curvature by a processing machine such as an NC lathe, and there is a gap L required for the electrical discharge machining conditions between the machined surfaces of the conductive grinding tool 1 held on the rotating shaft 23. Adjustment and setting are performed by moving the upper housing 20 more precisely using a moving device provided in the upper housing 20 so that the upper housing 20 can be placed in the desired position.

In connection with this seven-throat operation, the pump P of the supply section 29,
is operated to feed the electrical discharge machining fluid 28 into the machining tank 26 until both tools 1 and 11 are buried in the electrical discharge machining fluid 28.

After that, the motors 24 and 25 are operated to rotate the rotating shaft 22.
．． 23 is rotated, and an anode is applied from the power supply unit 40 to the conductive grinding tool 1 via the power supply brush 41, and a cathode is applied to the conductive reference tool 11 via the power supply brush 42, thereby performing electrical discharge machining. Conductive grinding tool 1
The spherical surface of the conductive reference tool 11 facing the is transferred onto each grindstone 2 of the conductive grinding tool 1 .

Further, in connection with the end of the electric discharge machining, the electric discharge machining liquid 28 in the machining layer 26 is drained from the discharge pipe 35 by opening the valve 32.
The water is recovered to the supply section 29 via the.

Then, the conductive grinding tool 1 and the conductive reference tool 11 are moved through the relative movement device of the upper housing 20.
After adjusting the conductive reference tool 11 while moving it relative to the conductive grinding tool 1 in order to set it with a gap 12 required for the electrolytic dressing conditions between both surfaces of the tool,
The rotating shafts 22 and 23 are rotated by the operation of the motors 24 and 25, and an electrolytic solution or weakly conductive coolant 30 is supplied between the conductive grinding tool 1 and the conductive reference tool 11 from the supply section 31 via the supply pipe 36. , and power supply section 40
By applying the anode and cathode of a DC power source to both tools 1.11 through the power supply brush 4142, each grinding wheel 2 surface of the conductive grinding tool 1 can be electrolytically dressed.

The electrolytic trestling was performed while supplying the electrolytic solution or the weakly electric coolant 30 between the two tools 111 via the supply vibrator 36, but it is also possible to perform the electrolytic trestling with the tool 111 filled until it is completely buried.

In addition, both tools 1.1 are used for electrical discharge machining and electrolytic dressing.
In addition to the state in which the parts 1 and 1 are rotated relative to each other, it is also possible to carry out the work with either one or both stopped.

The electrolytic solution or weakly electrolytic coolant 30 during or after the electrolytic dressing is recovered into the supply section 31 via the discharge vibrator 37 when the valve 33 of the processing tank 26 is opened.

〔Example〕

Embodiments of the present invention will be specifically described below with reference to the drawings.

(First Embodiment) FIGS. 3 to 6 show the first embodiment of the method and apparatus of the present invention, and FIG. 3 is an explanatory diagram showing the overall configuration of the apparatus;
FIG. 4 and FIG. 5 are explanatory diagrams showing electrolytic dressing.

3 to 5, the same components as those in FIG. 1 of the cylinder are designated by the same reference numerals, and description of each component will be omitted.

The upper and lower housings 20 and 21 each have a rotating shaft 222.
The bearing that rotatably receives the hair ring 4344.
45, 46, and a rotating shaft 22, 23, connecting pulleys 47, 48, and a drive boob IJ of the motor 24, 25.
49.50 and the motor 24.25 via a tension band 5152 stretched between each pulley 47, 48, 49.50.

Further, the power supply unit is constituted by an AC power supply unit 53 and a DC power supply unit 354, and each electrode of both power supply units 53.5d is connected to the conductive grinding tool 1 through a power supply brush 41.42.
and electrically connected to the conductive reference tool 11.

Further, each of the power supply units 53 and 51 includes a power supply unit 555.
6. Install voltmeters 57 and 58 and install AC
The power supply section 53 is provided with an ON/OFF switch 59, and the DC power supply section 54 is provided with a variable resistor 60, respectively.

Now, a method for electrical discharge and electrolytic machining of each grindstone 2 of the conductive grinding tool 1 using the electrical discharge and electrolytic machining apparatus for machining a grinding tool having the above configuration will be described below. first,
The machining surface of the conductive reference tool 11 held on the rotary shaft 22 has been precisely machined into a spherical surface with a machining curvature in advance by a processing machine such as an NC lathe, and the conductive grinding tool 1 held on the rotary shaft 23 is machined with precision. Gap E between surfaces required for electrical discharge machining conditions
, and place the top housing 2 so that it is fully aligned.
Adjustments are made while precisely moving by a moving device prepared for zero.

In connection with this seven-way operation, the pump P1 of the supply section 29 is operated to feed the electrical discharge machining fluid 28 into the machining tank 26 until both tools 1 and 11 are submerged in the electrical discharge machining fluid 28. Note that when supplying this electrical discharge machining fluid 28, the machining tank 2
6 valves 32,33 are closed.

Thereafter, the motors 24.25 are operated to rotate the rotating shaft 22.25.
23, the changeover switch 59 of the AC power supply unit 53 is turned on, and the anode is applied in pulses to the conductive grinding tool 1 via the power supply brush 41, and the cathode is applied to the conductive grinding tool 1 via the power supply brush 4.
By applying pulses to the conductive reference tool 11 via the conductive reference tool 2, the machining curvature spherical surface (R shown in the second figure) of the conductive reference tool 11 facing the conductive reference tool is created by electrical discharge machining.
) is transferred and created on each grindstone 2 of the conductive grinding tool 1. The application of electrodes from the AC power source 53 to each tool 1.11 is controlled by an ammeter 55 and a voltmeter 57 corresponding to the optimum electrical discharge machining conditions via a control section (not shown). Implemented.

Further, in connection with the end of the electric discharge machining, the electric discharge machining fluid 28 in the machining layer 26 is drained from the discharge pipe 35 by opening the valve 32.
The water is recovered to the supply section 29 via the. The valve 32 is closed until all of the electrical discharge machining fluid 28 in the machining tank 261ζ is recovered.

Then, the conductive grinding tool 1 and the conductive reference tool 11 are moved through the relative movement device of the upper housing 20.
After adjusting and setting the conductive reference tool 11 while relatively moving it with respect to the conductive grinding tool 1 in order to set the cast with a gap 12 required for the electrolytic dressing conditions between both surfaces of the
The rotating shafts 22 and 23 are rotated by the operation of the motors 24 and 25, and as shown in FIG. 11, and by applying the anode and cathode of DC power to both tools 1 and 11 from the DC power supply section 54 via the power supply brushes 41 and 42, respectively, the two surfaces of each grinding wheel of the conductive grinding tool 1 are Dressing can be done by electrolysis.

By this electrolytic dressing, the machined surface of each grindstone 2 of the conductive grinding tool 1 can be sharpened to a state with good workability (so-called cutting state).

Incidentally, when the valve 32 of the machining tank 26 is closed due to the completion of recovery of the electrical discharge machining fluid 28, the valve 33 is opened, and the supply pipe 36 interposes the tool 2 in the gap between the two tools 1 and 11. Electrolyte solution or weakly electric coolant]・30 is the fifth
As shown in the figure, it is collected into the supply section 31 via the discharge pipe 37. In addition, each supply section 29.31 recovered in this way
Each liquid 28, 30 is supplied to the processing tank 26 again after being subjected to appropriate treatment (for example, filter treatment) so that it can be reused.

Further, the electrolytic dressing is performed by supplying an electrolytic solution or a weakly electric coolant 30 to both tools 1 and 1 through a supply pipe 36.
Although the process was carried out by supplying the electrolytic solution or the weakly conductive coolant 30 to the machining tank 26 until both tools 1 and 11 were buried as shown in FIG. It is possible.

In addition, when applying the electrodes to both tools 1 and 11 from the DC power supply section 54, similarly to the application from the AC power supply section 54, a variable resistor 60. The ammeter 56 and the voltmeter 58 are controlled through a control section (not shown). Note that when the DC power supply section 54 is applied, the five changeover switches of the AC power supply section 53 are turned OFF.
FF.

However, in some cases, electrolytic dressing may be
It is also possible to use an AC power source using 3.

Therefore, a holding device for the conductive grinding tool l and the conductive reference tool 11, a drive device for the rotating shaft 22, 23, an electric discharge machining fluid 28, an electrolytic solution, or a weakly electrically conductive grinding tool necessary for performing the electrical discharge machining and electrolytic dressing described above. Coolant 30 supply parts 29, 31. AC and DC power supply section 53.54
In addition to the control of each device and each part, and other controls related to each of these devices and each part, the control required for the electrical discharge machining and electrolytic dressing, such as the timing between each device and each part, is controlled by a control (not shown). By controlling through the grinding section, it is possible to continuously and automatically perform the above-described generation processing and sharpening processing on the processing surface of the grinding tool 1.

(Second Embodiment) In the configuration of the first embodiment, the conductive reference tool 8 and the tool 11 are rotated, while the conductive grinding tool 1 is stopped while performing the electrical discharge machining and electrolytic dressing. In this case as well, the same effects as in the first embodiment can be obtained.

Further, contrary to the embodiment described above, it is also possible to stop the conductive reference tool 11 and rotate the conductive grinding tool 1, and the same effect can be obtained.

Furthermore, it is possible to perform electric discharge machining and electrolytic dressing while both tools 1 and 11 are stopped, but this method is inferior to the above-mentioned embodiments in terms of maintaining the machined surface shape of the conductive reference tool 11. .

In the above implementation, especially in the case of electrolytic dressing, the gap p between both tools 1.11 is ! We have compared and examined the effects of the cases in which the electrolytic solution or weakly electric coolant 30 shown in Figure 4 is supplied to the machining tank in each of the following examples, especially when performing electrolytic dressing. 2
In this study, a predetermined amount of oil is pumped into the electrolytic solution or the weakly electric tarant 30, and electrolytic dressing is performed.

Other conditions are the same as in the first embodiment.

Therefore, in an embodiment in which one of the two tools 1, 11 is stopped and the other is rotated, it can be carried out with the same effect as the first embodiment, but both tools 1.1
It has been found that the electrolytic dressing under the configuration shown in FIG. 4 when the tool 1 is stopped is inferior to the previous example in terms of maintaining the machined surface condition of the tool 11.

(Effects of the Invention) According to the present invention, a series of operations and processes from creating the shape of the grinding wheel surface of an optical lens grinding tool, etc. to so-called dressing (dressing) to make it ready for cutting can be performed manually within the same device. It can be done quickly without any problems, preserving the working environment,
It is also effective for beautification.

Moreover, compared to the conventional sharpening by lapping with loose abrasive grains, the dressing is performed with almost no dropout of abrasive grains such as diamond, so a grinding tool that can cut easily can be provided.

[Brief explanation of drawings]

Figures 1 and 2 are conceptual diagrams of the present invention, Figures 3 to 5
The figure shows the first embodiment of the present invention, FIG. 3 is an explanatory diagram of the overall configuration, FIGS. 4 and 5 are explanatory diagrams of the same electrolytic dressing, and FIGS. 6 to 9 are conventional grinding and polishing methods. Also, it is an explanatory view showing a method for creating and sharpening a machined surface of a grinding and polishing tool. 1... Conductive grinding tool 2... Grinding wheel 3... Tool plate 4... Adhesive 11... Conductive reference tool 20.21... Upper and lower housing 22. 23... Rotating shaft 24 , 25... Rotation drive motor 26... Machining shaft 27... Insertion part 28... Electric discharge machining fluid 29.31... Supply part 30... Electrolyte solution or weakly electric coolant 3233...
- Valve 34.36... Supply valve 35.37... Discharge pipe 40... Power supply section 41.42... Power supply brush 43.44, 45.46... Bearing 47, . 1
8... Connection pulley 49.50... Drive pulley 51.52... Tension band 53... AC power supply section 54... DC power supply section 55, 56... Ammeter 57.58... Volt meter 59...Switch 60...Variable resistor

Claims (3)

[Claims] (1) A conductive grinding tool and a conductive reference tool for creating a machined surface of the conductive grinding tool are rotated and made to face each other, and an anode is applied to the conductive grinding tool, and a cathode is applied to the conductive reference tool, respectively. By performing electrical discharge machining in an electrical discharge machining fluid, the predetermined shape of the electrically conductive reference tool is transferred onto the machining surface of the electrically conductive grinding tool, and the relative shape of the electrically conductive grinding tool and the electrically conductive reference tool is created. The machined surface of the conductive grinding tool is dressed by keeping the distance between the surfaces constant and supplying an electrolytic solution or a weak coolant between the opposing surfaces using a direct current. A method for creating a machined surface for a grinding tool. (2) A conductive grinding tool and a conductive reference tool for creating a machined surface of the conductive grinding tool are placed against each other, and an anode is applied to the conductive grinding tool, and a cathode is applied to the conductive reference tool, respectively. By performing electrical discharge machining in an electrical discharge machining fluid, the predetermined shape of the conductive reference tool is transferred onto the machining surface of the conductive grinding tool, and the relative surface of the conductive grinding tool and the conductive reference tool is A method for creating a machined surface of a grinding tool, comprising electrolytically dressing the machined surface of the conductive grinding tool in an electrolytic solution while maintaining a constant distance between the two and using a direct current. (3) A holding device for the conductive grinding tool and the conductive reference tool that rotatably and relatively moveably holds the conductive grinding tool and the conductive reference tool for creating a machining surface of the conductive grinding tool; A drive device for rotating and relatively moving a conductive grinding tool and a conductive reference tool, a control device for the drive device, an electrical discharge machining or dressing (dressing) machining bath for the conductive grinding tool and the conductive reference tool, and a processing tank for the conductive grinding tool and the conductive reference tool, a supply unit that supplies electrical discharge machining fluid to the tank; and a supply unit that supplies electrolyte or weakly conductive coolant between the machining tank or opposing surfaces of a conductive grinding tool and a conductive reference tool that are disposed relative to each other in the machining tank. . A machined surface creation device for a grinding tool, comprising: the conductive grinding tool; a DC power supply that applies an electrode to the conductive grinding tool; and an AC power supply unit.