JPH05185370A - Method and device for electrolytic dressing grinding - Google Patents

Abstract

PURPOSE:To adjust the electrolytic action of different points on a grinding tool by regulating the supplied amount of air to be mixed with a weak electric coolant, or by regulating the amount of coolant supply while the air supply is kept constant. CONSTITUTION:A member to be processed 4 a buts on a grinding tool 2 formed at the tip of a tool shank 1 which is rotatable. The member processed 4 is held by a retainer 3 engaged by a piece 5 in the form of an ornamental hairpin. The positive electrode of a DC power supply 7 is connected with the tool shank 1 by a feeder brush 6, while the negative electrode is connected with the hairpin piece 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic dressing grinding method and apparatus for preventing dressing unevenness in contour grinding of a workpiece such as a lens.

[0002]

2. Description of the Related Art Conventionally, as an electrolytic dressing grinding apparatus, for example, an invention described in Japanese Patent Laid-Open No. 43143/1993 has been disclosed. The above-mentioned invention, as shown in FIG.
A conductive grinding tool 91 having a hemispherical surface to be machined is attached to the tip of a rotary shaft 90 that is swingably held. The grinding tool 91 is formed of abrasive grains such as diamond powder with a conductive bond. Grinding tool 9
The processed surface of No. 1 has a processed member 92 having a shape corresponding to the processed surface.
Are in contact. The processed member 92 is the rotatable holding plate 9
It is held at 3. A ring-shaped electrode 94, which is set to have a slight gap 1 with the processing surface of the grinding tool 91 while holding the member to be processed 92, is attached to the outer periphery of the holding plate 93.

A pipe 96 for supplying a coolant 95 to the slight gap 1 is installed near the grinding tool 91 and the holding plate 93. A brush 98 connected to the anode of the DC power source 97 is in contact with the outer periphery of the rotating shaft 90.
Further, the cathode of the DC power source 97 is connected to the hook 99 that engages with the holding plate 94.

The apparatus having the above-mentioned structure rotates the holding tray 93 and rotates / swings the grinding tool 91. at the same time,
An anode is directly applied to the rotating shaft 90 and a cathode is applied to the electrode 94 from the power source 97, and the coolant 95 is supplied to the slight gap 1 for processing. At the time of this processing, electrolysis occurs on the processed surface of the grinding tool 91, and the processed surface of the grinding tool 91 can be ground while being dressed.

[0005]

However, in the above-mentioned prior art, although the ring-shaped negative electrode can act on the entire surface of the grinding tool during one-time machining, the negative electrode is formed in the shape of each point of the grinding tool. The time for which the electrodes act, that is, the time for performing electrolytic dressing at each point of the grinding tool differs depending on each point of the grinding tool. Furthermore, electrolysis proceeds more strongly as the peripheral speed of the grinding tool decreases. Therefore, the entire surface of the grinding tool is not electrolytically dressed uniformly, and the shape of the grinding tool cannot be maintained. Therefore, there is a problem in that as the machining progresses, the shape of the grinding tool collapses, and the shape accuracy of the member to be machined deteriorates.

Therefore, the present invention was developed in view of the above problems in the prior art. By supplying air together with a weak electric coolant and adjusting the supply amount of both or either one, the grinding tool is It is an object of the present invention to provide an electrolytic dressing grinding method and apparatus capable of adjusting the electrolytic action at each point in (1) to maintain the shape accuracy of the grinding tool.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a rotating conductive grinding tool is provided with an anode, and a ring-shaped electrode for keeping a constant distance from the work surface of the conductive grinding tool and surrounding a work is provided with a cathode. In the electrolytic dressing grinding method, in which the workpiece is machined while supplying a weak electric coolant between the conductive grinding tool and the electrode, while applying a voltage to each other to relatively slide the work along the machined surface of the conductive grinding tool A method of working while supplying air between the conductive grinding tool and the electrode together with the weak electric coolant.

Further, the rotating conductive grinding tool is provided with an anode,
Apply a cathode to each ring-shaped electrode that keeps a constant distance from the machined surface of the conductive grinding tool and surrounds the work,
In an electrolytic dressing grinding device that slides a workpiece relative to the machining surface of the conductive grinding tool and supplies the weakly electrically conductive coolant between the conductive grinding tool and the electrode, the electrolytic dressing grinding machine uses coolant and air. A means for adjusting the supply amount of at least one of the above, and a means for supplying the weakly conductive coolant and air between the conductive grinding tool and the electrode.

FIG. 1 is a conceptual diagram of an apparatus used in the present invention. The workpiece 4 is in contact with the electrically conductive grinding tool 2 formed in a convex spherical shape at the tip of the tool shaft 1 connected to a drive source (not shown). The member to be processed 4 is pressure-held by a swingable holder 3 having a recessed portion at the center opposite to the holding surface thereof, which engages with the spherical tip portion of the rod-shaped kanzashi 5. At the time of processing, the workpiece 5 is ground to a spherical surface by swinging the hammer 5 (direction of arrow A) while rotating the grinding tool 2.

An anode of a DC power source 7 for generating a pulse voltage is connected to the tool shaft 1 by a power feeding brush 6, and a cathode thereof is connected to the kanzashi 5. A liquid in which a weakly conductive coolant and air are mixed is jetted from arrows a1, a2, a3 and a4. Alternatively, arrows b1, b2, b3 and b4
Blow more. Alternatively, injection is performed from c1, c2 and c3. Alternatively, the weak electric coolant is injected from the arrows a2 and a3, and the air is injected from the arrows b1, b2, b3 and b4.

The action is to adjust the amount of air supplied from each arrow while keeping the amount of coolant supplied constant by utilizing the fact that the electrolytic action is lowered as the amount of air supplied to the weak electric coolant increases. Alternatively, adjusting the electrolytic action to each part of the grinding tool by interposing a mixed solution in which the amount of coolant supplied from each arrow is adjusted with a constant air supply amount between the negative electrode and the grinding tool of the anode, By maintaining the tool shape, it is possible to perform processing while maintaining the shape accuracy of the lens.

[0012]

Embodiment 1 FIGS. 2 and 3 show an apparatus used in this embodiment, FIG. 2 is a partial sectional view, and FIG. 3 is an end view taken along the line AA 'of FIG. Tool shaft 1 connected to a drive source (not shown)
The workpiece 4 is in contact with the electrically conductive grinding tool 2 having a convex spherical shape at its tip. The member to be processed 4 is pressure-held by a swingable holder 3 having a recessed portion at the center opposite to the holding surface thereof, which engages with the spherical tip portion of the rod-shaped kanzashi 5. At the time of processing, the workpiece 5 is ground to a spherical surface by swinging the hammer 5 (direction of arrow A) while rotating the grinding tool 2. The cathode of the DC power supply 6 that generates a pulse voltage is connected to the tool shaft 1 by the power supply brush 7, and the cathode is the above-mentioned kanzashi 5
It is connected to the.

The pipes 10a to 10f pass a liquid in which a weakly electric coolant supplied from the coolant 13 and air whose supply amount can be adjusted are supplied from the air pump 14 via valves 15a to f. The pipes 10a to 10f are fixed to a mixed liquid discharge member 9 connected to the holder 3 via a bearing 8. The mixed liquid discharge member 9 is a holder 3
Although it swings in conjunction with,
It is fixed via a spring 12 connected to the protrusion 5a.

In the grinding method using the apparatus having the above-mentioned structure, the electrolytic action is lowered as the amount of air supplied to the weak electric coolant increases. That is, the decrease in dressing is used. The mixed liquid of the coolant and air supplied to the mixed liquid discharge member 9 through the pipes 10a to 10f is
The mixture is ejected from the nozzle of the ejecting member 9 between the holding tool 3 acting as a negative electrode and the anode grinding tool 2. The amount of air in this mixed solution is controlled by the valves 15a to 15f so that the amount of air supplied to the entire surface of the grinding tool 2 is reduced in the portion where the electrolysis is strengthened and conversely is increased in the portion where the electrolysis is desired to be weakened. Adjust to. While interposing the mixed liquid adjusted in each part of the grinding tool 2 between the holder 3 and the grinding tool 2,
Electrolytic dressing is performed by the holder 3 applied to the cathode via the kanzashi 5 by the pulse power source and the grinding tool applied to the anode via the power feeding brush 7.

According to this embodiment, the electrolytic action of each part of the grinding tool can be adjusted, the shape of the grinding tool can be maintained, and the processing can be performed while maintaining the shape accuracy of the lens. it can.

In this embodiment, the air supply amount was adjusted by the valve, but conversely, the same effect was obtained by adjusting the coolant supply amount. Further, the above effect can be obtained if the number of nozzles of the mixed liquid ejection member 9 is at least two or more. Further, when it is desired to increase or decrease the strength of electrolysis, it is sufficient to supply only the grinding liquid from the nozzle in the portion where the strong action is desired and supply only the air from the nozzle in the portion where it is not desired to proceed.

[0017]

[Embodiment 2] FIG. 4 is a partially enlarged sectional view of an apparatus used in this embodiment. Most of the configuration of the present embodiment is common to that of the first embodiment, the common parts are denoted by the same reference numerals, the description thereof will be omitted, and different parts will be described.

The grinding tool 24 has at least one hole, such as holes a, b, and c, on the circumference for passing a mixture of coolant and air. The weak electric coolant supplied from a coolant tank (not shown) is branched into three, and is mixed with each pipe 20a to 20c through the air pump through a valve to adjust the supply amount. The pipes are ring-shaped mixed liquid supply members 21a to 21c each having a ring-shaped recess formed in the inner peripheral portion thereof.
Fixed to. The mixed liquid supply members 21a to 21c are fixed by a rod member 25 fixed to a tool shaft fixing base (not shown) such that the rotation shaft of the tool shaft 23 and the center of the shaft coincide with each other.

The holes a to c communicate with holes 23a to 23c provided in the tool shaft 23 to which the grinding tool 24 is attached. The holes 23a to 23c penetrate the outer circumference of the tool shaft 23, and a ring-shaped projection is formed in the opening thereof, and the periphery thereof is engaged with a recess provided in the mixed liquid supply member 21. However, a seal 22 is provided, which is slidable with respect to each other and used for sealing. Also, the tool axis 2
The tool shaft 23 and the grinding tool 24 are fixed so that the holes 23a to 23c of No. 3 coincide with the holes a to c of the grinding tool 24.

In the grinding method using the apparatus having the above-mentioned structure, first, a mixed liquid of coolant and air is used as the grinding tool 2
4 and the holder 3. The mixed liquid adjusts each air valve (not shown) in order to adjust the air supply amount of the holes a, b, c on each circumference of the grinding tool 24. The mixed liquids having different air amounts on the respective circumferences are connected to the pipes 20a ...
c, mixed liquid supply members 21a to 21c, each hole 23 of the tool shaft 23
a through c, passing through the holes a through c of the grinding tool 24, the holder 3
Intervenes between. Electrolytic dressing is performed by the holder 3 applied to the cathode via the kanzashi 5 by the pulse power source and the grinding tool 24 applied to the anode via the power feeding black.

According to this embodiment, the amount of the air supplied to the mixed liquid of the coolant and the air can be adjusted on each circumference, so that the holder 3 can be swung by the swinging movement of the siphon 5 (in the direction of arrow A). Even if the rocking of the grinding tool covers the entire surface of the grinding tool 2, it is possible to accurately discharge the air supply amount to the portion where the electrolysis is to be weakened or strengthened. Therefore, the shape of the grinding tool 2 is maintained even with such rocking. It is possible to perform dressing while maintaining the shape accuracy of the lens.

It should be noted that the number of rows of holes a to c was three on the circumference of the grinding tool 24, but if there are two or more, the same effect as above can be obtained.

[0023]

Third Embodiment FIGS. 5 and 6 show an apparatus used in this embodiment, FIG. 5 is a partial sectional view, and FIG. 6 is an end view taken along the line BB 'of FIG. Most of the configuration of the present embodiment is common to that of the first embodiment, the common parts are denoted by the same reference numerals, the description thereof will be omitted, and different parts will be described.

The air discharge member 30 is an air pipe 31a.
~ F, and is fixed via the spring 12 and the protruding portion 5a of the Kanzashi 5. Further, the same swing as the swing of the holder 3 is performed via the bearing 8. Coolant is discharged from the nozzle 32 between the grinding tool 2 and the holder 3. The amount of air supplied to the air pipes 31a-f is controlled by the valves 33a-f.
Adjust by.

In the grinding method using the apparatus having the above structure, the grinding tool 2 is directly blown with air to carry out the processing.

According to the present embodiment, the strength of electrolysis is extremely increased for each part of the grinding tool.

[0027]

Fourth Embodiment FIGS. 7 and 8 show an apparatus used in this embodiment, FIG. 7 is a partial sectional view, and FIG. 8 is an end view taken along the line CC ′ of FIG. 7. Most of the configuration of this embodiment is the same as that of the first embodiment.
Common parts are denoted by the same reference numerals, description thereof will be omitted, and different parts will be described.

For the grinding tool 44 having conductivity, which is formed in a concave spherical shape at the tip of the tool shaft 1, the workpiece 4 is
Are in contact. The workpiece 4 is pressure-held by a swingable holder 43. Pipes 10a-f
Is fixed to the negative electrode 40 connected to the holder 43 via the bearing 8. The negative electrode 40 is a holder 43.
Although it swings in conjunction with,
It is fixed via the protrusion 5 a and the spring 12. Also,
An insulator brush 42 is fixed to the lower surface of the negative electrode 40 so as to divide the nozzles 40 a to 40 f of the negative electrode 40.

In the grinding method using the apparatus having the above structure, the mixed liquid with the coolant whose air supply amount is adjusted by each of the pipes 10a to 10f is supplied to the nozzle portion 40a of the negative electrode 40.
Discharge between the tool and the grinding tool 2. Each nozzle 4
The mixed liquids having different amounts of air discharged from 0a to 0f are present between the negative electrode 40 and the grinding tool 44 without being mixed with each other by the insulator brush 42, and are applied to the cathode by the pulse power source. And electrolytic grinding is performed with the grinding tool 44 applied to the anode via the power supply brush 7.

According to this embodiment, the electrolytic action of each part of the grinding tool can be finely adjusted, the shape of the grinding tool can be maintained more than in the first embodiment, and the shape accuracy of the lens can be maintained. While processing can be performed.

In this embodiment, the mixed liquid of air and coolant is used. However, only the grinding liquid is supplied from the nozzle in the portion where electrolysis is desired to be maximized, and only the air is supplied from the nozzle in the portion where electrolysis is not desired to proceed. By supplying, the strength of electrolysis is further increased.

In each of the above embodiments, an example of processing a single lens is shown, but the same effect can be achieved even with a multi-attached lens or a multi-attached grinding wheel or polishing wheel. Further, the lens holding and swinging means is not limited to the kanzashi. Further, the swing between the lens and the grindstone is relative, and can be performed by swinging on the tool shaft side.

[0033]

As described above, according to the electrolytic dressing grinding method and apparatus of the present invention, the amount of air supplied to the weakly electrically conductive coolant is adjusted, or the amount of air supplied is kept constant. By adjusting
The electrolytic action at each point of the grinding tool can be adjusted, stable sharpening can be promoted without the shape of the grinding tool being collapsed, and grinding can be performed in which the machined surface of the workpiece is finished well.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the present invention.

FIG. 2 is a partial cross-sectional view showing the first embodiment.

FIG. 3 is an end view taken along the line AA ′ of FIG.

FIG. 4 is a partially enlarged cross-sectional view showing a second embodiment.

FIG. 5 is a partial cross-sectional view showing a third embodiment.

FIG. 6 is an end view taken along line BB ′ of FIG.

FIG. 7 is a partial cross-sectional view showing a fourth embodiment.

FIG. 8 is an end view taken along line CC ′ of FIG. 7.

FIG. 9 is a partial cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 Tool Axis 2 Grinding Tool 3 Holding Tool 4 Workpiece Material 5 Kanzashi 6 Power Supply Brush 7 DC Power Supply

Claims (1)

[Claims] 1. A method for machining a conductive grinding tool, wherein an anode is applied to a rotating conductive grinding tool, and a cathode is applied to a ring-shaped electrode that surrounds a workpiece while maintaining a constant distance from a machining surface of the conductive grinding tool. In the electrolytic dressing grinding method in which the work is relatively slid along the surface and the work is processed while supplying the weakly electric coolant between the conductive grinding tool and the electrode, air is electrically conducted together with the weak electric coolant. Electrolytic dressing grinding method, characterized in that it is processed while being supplied between a conductive grinding tool and an electrode. 1. A method for machining a conductive grinding tool, wherein an anode is applied to a rotating conductive grinding tool, and a cathode is applied to a ring-shaped electrode that surrounds a workpiece while maintaining a constant distance from a machining surface of the conductive grinding tool. In an electrolytic dressing grinding device that processes a work while sliding the work relatively along the surface and supplying a weakly electric coolant between the conductive grinding tool and the electrode, at least one of coolant and air An electrolytic dressing grinding apparatus comprising: a means for adjusting a supply amount; and a means for supplying the weakly conductive coolant and air between the conductive grinding tool and an electrode.