JPH06134671A - Grinding wheel dressing and device therefor - Google Patents

Abstract

PURPOSE:To minimize a dressing electric source in the cross direction to meet blinding force of a grinding wheel in the cross direction and prolong the life of the grinding wheel. CONSTITUTION:By dividing a dressing electrode 2 provided facing against the surface of a grinding wheel 1 in the cross direction of the grinding wheel 1 and by changing values and frequency of electric currents flowing to each of the divided electrodes 2, distribution of dressing force is given in the cross direction of the grinding wheel 1. Consequently, in a device to carry out machining of a ground material while applying the electric current to the grinding wheel 1 holding a super-abrasive grain grinding wheel by a conductive bond, it is possible to carry out dressing of the wide grinding wheel 1 which is conventionally hard to carry out electric dressing on by in-process without increasing dressing electric source capacity and to keep a favourable cutting edge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding process for simultaneously performing grinding wheel dressing and grinding by electric action.

[0002]

2. Description of the Related Art When a grindstone used for grinding is continuously used, a part of shavings is mixed between abrasive grains, or a work material is welded to the grindstone and becomes clogged, resulting in a significant decrease in cutting efficiency. To do. Therefore, it is necessary to interrupt the grinding as needed to remove the working surface of the grindstone with an appropriate tool to make a sharp cutting edge appear, and such work is called dressing.

Under these circumstances, a dressing method called an in-process dressing method has been devised as a method of performing dressing without interrupting the processing of a workpiece, and the outline thereof will be described below.

In-process dressing uses a grindstone obtained by hardening diamond or CBN particles with a conductive bond.
It is a method of performing dressing by generating an electric conduction state between the surface of a grindstone independently from the processing of a workpiece. The dressing electrodes are arranged facing each other on the peripheral end face of the grindstone that is separated from the contact portion with the workpiece, and electricity is passed between the conductive grindstone and the electrode through the electrolytic solution. As the current pattern, there are a direct current with the grindstone side as a positive electrode, a pulse current and an alternating current with different poles, each having different dressing characteristics, and the optimum dressing current differs depending on the grindstone bond material and required grinding characteristics. For example, in a grindstone using a bond that does not generate a non-conductive film, the electrolytic deposition amount increases and the dressing force increases by increasing the current value. Further, in a bond material in which a non-conductive film is generated by electrolysis, using a pulse current causes the non-conductive film to be broken and the dressing force to increase.

Further, in Japanese Unexamined Patent Publication No. 3-239473, as shown in FIGS. 6 and 7, in a cup-shaped grindstone, a difference in peripheral speed occurs between the outer peripheral portion and the inner peripheral portion of the grindstone, and the electrolytic elution amount in the width direction. Therefore, a method is adopted in which the electrodes are divided so that the electrolytic elution amount is constant. As described above, the conventional technique performs dressing so that the dressing force in the width direction of the grindstone is constant.

[0006]

In the case of a whetstone with a narrow whetstone width, there is no problem even if the dressing force in the whetstone width direction is constant, but if a wide whetstone is used, the clogging of the whetstone will occur in the whetstone width direction. It becomes uneven. For example, it is likely to occur at the end of the grindstone, and due to the fact that chips are caught or the electrolyte is cut off, clogging may suddenly occur even at the center of the grindstone. In the conventional dressing method, in order to carry out uniformly in the width direction of the grindstone, it is necessary to adjust the dressing force to the place where the eyes are most likely to be clogged, and the same electrolytic force is applied to the well-marked part of the grindstone. In the case of a whetstone having a wide whetstone, the dressing device has a large capacity. In addition, excessive dressing elutes the bonding agent to accelerate the removal of abrasive grains and shorten the life of the grindstone.

The present invention solves the above-mentioned conventional problems, the dressing force in the width direction can be adjusted to match the clogging force in the width direction of the grindstone, and the dressing power source can be reduced.
Moreover, it is an object of the present invention to provide a dressing method and apparatus that can prolong the life of a grindstone.

[0008]

The gist of the present invention is as follows. (1) The dressing electrode provided facing the grindstone surface was divided in the grindstone width direction, and the distribution of the dressing force was provided in the grindstone width direction by changing the current value and the frequency of the current flowing through each of the divided electrodes. A whetstone dressing method characterized by the above. (2) A dressing electrode is provided so as to face the grindstone surface, the electrode is divided in the grindstone width direction, and a dressing power supply that can change the value of the current flowing through each divided electrode or change the frequency of the current is provided. A grinding wheel dressing device characterized by having a distribution of dressing force in the grinding wheel width direction.

(3) The dressing electrode provided facing the grindstone surface is divided in the grindstone width direction, and the distance between each of the divided electrodes and the grindstone is changed to give a distribution of dressing force in the grindstone width direction. Whetstone dressing method characterized by. (4) The dressing electrode is provided facing the grindstone surface, the electrode is divided in the grindstone width direction, the dressing electrode provided facing the grindstone surface is divided in the grindstone width direction, and the divided electrodes and grindstone A grindstone dressing device characterized in that each electrode is provided with an electrode drive device for changing the interval, and an electrolytic force is distributed in the grindstone width direction.

(5) It is possible to strengthen the dressing at any place by moving not only the electrode which performs dressing in the width direction of the grindstone evenly, but also the electrode which is provided with a driving device which moves in the width direction of the grindstone. A whetstone dressing method characterized by being able to do. (6) A dressing electrode is provided facing the grindstone surface, and in addition to an electrode that performs dressing evenly in the grindstone width direction, an electrode provided with a driving device that moves in the grindstone width direction is provided facing the grindstone, A grindstone dressing device characterized by being able to enhance dressing at any place.

[0011]

[Function] By forcibly giving the distribution of the dressing force in the width direction of the grindstone, the dressing force can be adjusted according to the strength of the clogging, and the capacity of the power supply used for dressing can be minimized. Since the useless removal of the abrasive grains does not occur, the life of the grindstone is extended.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The dressing method and apparatus of the present invention will be described in detail below with reference to the drawings by taking traverse cylindrical grinding as an example. The in-process dressing method is as shown in FIG. 1, in which electricity is supplied from the power source 3 between the grindstone 1 and the electrode 2 installed facing the grindstone so that the grindstone serves as a positive electrode and the electrode serves as a negative electrode, thereby clogging the surface of the grindstone. The chips are removed by an electric action such as electrolysis or electric discharge, and the workpiece 4 is ground at the same time. In order to perform an electrical action, the electrolyte is supplied from the nozzle 5 between the electrode 2 and the grindstone 1. There are a method of supplying the electrolytic solution by a nozzle provided outside and a method of supplying the electrolytic solution by a hole provided in the dressing electrode. The feature of the present invention is that the distribution of the dressing force is provided in the axial direction of the grindstone.

An example thereof is shown in FIG. The electrode 2'contacting the grindstone 1 is divided and an insulator 6 is inserted between the electrodes. Connect the negative electrode of the power supply 3'that can control the current condition to the electrode, connect the positive electrode of the power supply to the grinding stone, and change the current condition flowing to each electrode to give the dressing force a distribution in the axial direction of the grinding stone. . When a direct current is used as the dressing current, the dressing force increases as the current value increases, and the dressing force decreases as the current value decreases. When a pulse current or an alternating current is used as the dressing current, the dressing force can be increased or decreased by changing the frequency.

As shown in FIG. 3, there is also a method of controlling the dressing force by changing the gap between the grindstone 1 and the electrodes by a driving device 7 installed on the divided electrodes 2'without changing the current flowing through the divided electrodes. By bringing the electrode of the portion a for which the dressing force is desired to be strengthened closer to the grindstone, the resistance between the grindstone of the portion a and the electrode is lowered, the current value is locally increased, and the dressing force is increased. On the contrary, when the dressing force is weakened, it can be weakened by increasing the distance between the grindstone and the electrode.

As shown in FIG. 4, there is also a method in which the electrode is not divided and the fixed electrode 2 is uniformly dressed, and the moving electrode 2 ″ is moved in the grindstone width direction by the drive unit 8 to strengthen the dressing. When the width of the dressing electrode in the circumferential direction becomes wider, the amount of current supplied to that portion increases and the dressing force is strengthened.

Regarding the distribution of the dressing force in the width direction of the grindstone, in the case of the traverse cylindrical grinding shown in FIG. 5, if the grindstone is moved from a to the right side of b during grinding, the grinding load on the right side of the grindstone increases and the grindstone on the right side of the grindstone. Are easily clogged. Therefore, effective dressing can be performed by strengthening the dressing force on the right side of the grindstone. When the grindstone is moved to the left side, it is necessary to strengthen the left side of the grindstone. The width of the grindstone to be strengthened depends on the grinding conditions such as the traverse speed, the diameter of the work material, and the cutting depth.

Further, in the case of a wide-width grindstone, it is difficult to manufacture the grindstone by evenly distributing the abrasive grains in the width direction, and a portion where the abrasive grains are dense is always clogged. In that case, a distribution of the dressing force is given in advance so as to strengthen the dressing of that portion.

[0018]

EFFECTS OF THE INVENTION By using the method and apparatus of the present invention, in an apparatus for processing a work material while applying a current to a grindstone in which a superabrasive grindstone is held by a conductive bond, conventional electrical dressing has been used. Even a wide grindstone, which was difficult, can be dressed in-process without increasing the dressing power supply capacity, and good cutting edge can be maintained.
In addition, since the grindstone is not subjected to unnecessary dressing, the life of the grindstone is extended. And so on.

[Brief description of drawings]

FIG. 1 is a side view of an in-process dressing device according to the present invention.

FIG. 2 is an explanatory diagram of an embodiment of arrangement between grindstone electrodes.

FIG. 3 is an explanatory view of an example of the arrangement between the grindstone electrodes.

FIG. 4 is an explanatory diagram of an example of the arrangement between the grindstone electrodes.

FIG. 5 is a diagram at the time of traverse grinding.

FIG. 6 is an example of a conventional method in which the electrodes of a cup-shaped grindstone are divided.

FIG. 7 is an example of a conventional method in which electrodes of a cup-shaped grindstone are divided.

[Explanation of symbols]

 1 Grindstone 2 Electrode 3 Power Supply 4 Work Material 5 Nozzle 6 Insulating Material 7 Grindstone Radial Drive Device for Electrode 8 Grindstone Width Drive Device for Electrode

Claims (6)

[Claims] 1. A method for processing a work material at the same time by applying an electric action to a grindstone having superabrasive grains such as diamond and CBN fixed by a conductive bond to prevent clogging of the grindstone It is characterized in that the dressing electrodes provided facing each other are divided in the width direction of the grindstone, and the distribution of the dressing force is given in the width direction of the grindstone by changing the current value or the frequency of the current flowing through each of the divided electrodes. Whetstone dressing method. 2. A dressing device for processing a work material at the same time by applying an electric action to a grindstone in which superabrasive grains such as diamond and CBN are fixed by a conductive bond to prevent the grindstone from being clogged. The electrode is provided facing the grindstone surface,
The grindstone is characterized by dividing the electrode in the grindstone width direction and equipped with a dressing power source that can change the current value and the frequency of the current flowing through each of the divided electrodes, and giving a distribution of dressing force in the grindstone width direction. Dressing equipment. 3. A method of processing a work material at the same time by applying an electric action to a grindstone in which superabrasive grains such as diamond and CBN are fixed by a conductive bond to prevent clogging of the grindstone The dressing electrode provided so as to face each other is divided in the grindstone width direction, and the distance between each of the divided electrodes and the grindstone is changed to give a distribution of dressing force in the grindstone width direction. 4. A dressing device for processing a work material at the same time by applying an electric action to a grindstone having superabrasive grains such as diamond and CBN fixed by a conductive bond to prevent the grindstone from being clogged The electrode is provided facing the grindstone surface,
The electrode is divided in the grindstone width direction, the dressing electrode provided facing the grindstone surface is divided in the grindstone width direction, and each electrode is equipped with an electrode drive device that changes the distance between each divided electrode and the grindstone. A grindstone dressing device characterized in that it has an electrolytic force distribution in the width direction. 5. A method for processing a work material at the same time while applying a mechanical action to a grindstone in which superabrasive grains such as diamond and CBN are fixed by a conductive bond to prevent clogging of the grindstone In addition to the electrodes that perform dressing evenly in the direction, by moving the electrode provided with a drive device that moves in the width direction of the grindstone, it is possible to strengthen the dressing at any place, the grinding wheel dressing method characterized in that . 6. A dressing device for processing a work material at the same time by applying an electric action to a grindstone in which superabrasive grains such as diamond and CBN are fixed by a conductive bond to prevent the grindstone from being clogged. The electrode is provided facing the grindstone surface,
In addition to the electrodes that perform dressing evenly in the width direction of the grindstone,
A grindstone dressing device, characterized in that an electrode having a drive device for moving in the grindstone width direction is provided so as to face the grindstone so that dressing at any place can be strengthened.