JPH0238347B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for regenerating a metal bonded grinding wheel, and more particularly to a method for performing discharge truing or discharge dressing of a metal bonded grinding wheel. .

[Prior Art] Conventionally, a method of regenerating a metal bonded grinding wheel by electric discharge truing or electric discharge dressing is already known.

However, in the above-mentioned known method, as the truing and dressing proceed, the electrode tool wears out and the shape of the electrode tool is disturbed, so the shape accuracy of the grinding wheel surface that is finally formed by transferring the shape of the electrode tool is However, it is not always possible to obtain an appropriate regenerated surface of the grindstone, and in particular, it is very difficult to obtain a regenerated surface of the whetstone with good shape accuracy in-process. Further, even if some means is applied to the processing electrode to avoid the negative effects of electrode wear, it is necessary to use a high-precision guide device such as an NC device to guide the electrode.

[Problems to be Solved by the Invention] The present invention utilizes a wire that is successively fed out to an electrode tool for performing discharge truing or discharge dressing of a grinding wheel, and sweeps the working surface of the grinding wheel, thereby achieving a desired result. It is an object of the present invention to provide a method for regenerating a metal bonded whetstone in which the working surface of the whetstone can be regenerated into the shape of , and at the same time, the regeneration can be carried out in-process with high accuracy using a simple device.

[Means for Solving the Problems] A grindstone regeneration method of the present invention for achieving the above object includes supporting discharge electrode wires arranged in parallel at a constant pitch on a wire support consisting of a roll or a template. Then, these wire rows are placed opposite the working surface of the metal bond grinding wheel, and while the wires are fed out from one end and wound in from the other end, the wire rows are aligned along the grinding wheel working surface and the orientation of each wire is adjusted. By applying a voltage between the wire and the grindstone while moving them relative to each other in a direction that intersects with the
This is characterized in that discharge truing or dressing of the grindstone is performed by discharge between the two.

[Operation] In the above regeneration method, an electrode tool for performing discharge truing or discharge dressing of a metal bonded grindstone is formed by a row of parallel discharge electrode wires with a constant pitch, and the electrode tool is used to cover the grindstone working surface. Sweeping regenerates the grindstone working surface into the desired shape. In this case, since the above-mentioned parallel wire rows are especially used, the electrode tool is updated one after another by winding the wire, correcting the shape disturbance due to electrode wear, and also making it easy to regenerate the grindstone. The equipment allows it to be done in-process.

[Example] Fig. 1 schematically shows an outline of an apparatus for regenerating a grindstone by the method of the present invention. A state in which an electrode tool 4 for grindstone regeneration, which will be described below, is arranged at a position that does not interfere with grinding, for example, at a position around the grindstone 2 on the opposite side of the workpiece 3 is shown.

The electrode tool 4 can have various configurations depending on the shape of the grindstone 2, and the electrode tool 4 for grindstone regeneration illustrated in FIG. 8 is wrapped around it to hold it. Therefore, the wire 8 is placed on the surface of the roll 6.
are arranged in parallel at a certain pitch,
When the roll 6 is rotated about an axis parallel to the rotation axis of the grindstone 2, the row of wires 8 appears to move in parallel on the surface of the roll 6 as the roll 6 rotates. The wire 8 may be fed out from the roll 6 and wound in by an endless wire, or may be wound around a feeding roller and a winding roller (not shown). The discharge electrode wire 8 and the metal bond grindstone 2 are connected to a power source 9 for discharge.

When regenerating the grindstone, with the wire row facing the working surface of the metal bonded grinding wheel 2, a voltage is applied between them and the roll 6 is slowly rotated, so that the grindstone 2 is aligned with the direction of the wire 8. There is a relative movement in the transverse direction, whereby the wire 8 sweeps over the grinding wheel working surface, during which the grinding wheel 2 is subjected to discharge truing or discharge dressing by the voltage.

Such discharge truing or discharge dressing can be easily performed in-process, by simply performing truing to cope with the wear of the grinding wheel during grinding, or dressing to renew the necessary cutting edge. This does not preclude it from being carried out independently of grinding.

In the discharge truing or discharge dressing described above, in order to compensate for the wear and tear of the electrode tool 4,
The shape accuracy of the electrode tool is maintained by the cylindrical surface of the roll 6, and by winding the wire 8 by the rotation of the roll 6 by the amount by which the electrode has been worn out, the disturbance in shape due to the wear of the electrode tool is corrected. In this case, roll 6
When the wire 8 rotates once at a constant speed, the wire 8
is shifted by one pitch at a constant speed, so the discharge electrode wire 8 can be updated extremely smoothly.

When regenerating the grinding wheel 2 using such an electrode tool 4, there is no problem if the amount of electrical discharge machining is small and the number of rotations of the roll 6 is small, but if the amount of electrical discharge machining is large and the number of revolutions of the roll 6 is low, there is no problem. If the wire 6 only rotates but does not move in the axial direction, the wound portion of the wire 8 will gradually move in the axial direction, as shown in FIG. 2, and will not only come off the grindstone surface but also come off the roll 6. To solve this problem, the roll 6 may be made longer and the number of turns of the wire 8 may be increased at the same time, or the structure shown in FIG. 3 may be adopted. In the electrode tool shown in the figure, one end of a roll 10 supported slidably in the axial direction is inserted into a guide plate 11 supported by a fixed part, and the roll 10 is connected to a wire 12 as shown by an arrow a. Pressure is applied from the winding side to the unwinding side, and the wire 12 is always slid along the guide plate 11 on the unwinding side due to the pressing force and is wound up. Therefore, the roll 10 is moved by the amount that the wrapped portion of the wire 12 is moved on the roll 10.
is moved in the axial direction by the pressing force, and the wrapped portion is prevented from coming off the grindstone surface.

When the amount of electrical discharge machining is even larger, not only a single roll but also a plurality of rolls 10a and 10b can be successively switched and used.

4 to 6 show examples of application of the electrode tool 4 to various types of grinding wheels. FIG. When the peripheral surface of the grindstone 15 is to be regenerated, FIG. 6 shows a case in which the end surface of the stick-shaped grindstone 16 is to be regenerated.

In addition, when regenerating the above-mentioned whetstone, if the whetstone is
The present invention can be applied not only to the case of a simple cylindrical or conical surface as shown in the figure, but also to a grindstone 20 having a curved surface as shown in FIG. In this case, the shape of the roll described above may be modified to match the shape of the grinding wheel 20 having a curved surface, or if the shape of the grinding wheel is relatively simple, the roll 21 may be modified as shown in FIG. is held in a curved state by an elastic body, and while maintaining this curved state, the flexible shaft 2 is
It is also possible to rotate it by 2. However, in this case, it is necessary to provide reinforcement or the like so that the contact portion of the wire 23 on the surface of the roll 21 is not deformed by the tension of the wire 23.

In the electrode tool shown in FIG. 8, in order to accommodate a grindstone 20 having a complicated curved surface, a thin discharge electrode wire 27 is placed between two templates 25 and 26 corresponding to the shape of the grindstone. The wire 27 is tensioned by reciprocating it many times, and the wire 27 forms an electrode tool with a pseudo-curved surface. This wire 27 can be fed out from a feeding roll 31 and wound around a winding roll 32 to cope with wear and tear caused by electric discharge.

When using an electrode tool having such a configuration, the entire surface of the grindstone 20 can be regenerated as follows.

The first is that when the wire 27 is stretched between the two templates 25, 26, both the templates 25, 26
6, the position of the wire 27 is shifted by at least one pitch to support the wire 27, thereby supporting the grinding wheel 20.
A grindstone 20 is placed facing the curved surface formed by the wire 27, and in this state, the grindstone 20 is moved in the direction of arrow A with respect to the electrode.
direction (in a direction that is not shifted like the wire 27).

The second method is to stretch the wire 27 between the two templates 25 and 26 (there is no need to shift it by 1 pitch), thereby forming an electrode tool that matches the shape of the grinding wheel 20, and creating a curved surface formed by this wire 27. The grindstone 20 is placed facing the wire 27, and in this state, only the grindstone 20 and the templates 25, 26 are moved synchronously in the direction of arrow B, or they are fixed and the entire wire 27 is moved in the same manner.

By such an operation, truing or dressing by electric discharge is uniformly performed between the rotating grindstone and the electrode tool formed by the wire 27, and the grindstone is regenerated.

[Effects of the Invention] According to the regeneration method of the present invention, the wire that is successively fed out to the electrode tool for performing discharge truing or discharge dressing of the grindstone is used, so that the work surface of the grindstone can be regenerated to the desired state. At the same time, the regeneration can be performed in-process using a simple device and with high accuracy by feeding out the wire.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an outline of an apparatus for carrying out the grinding wheel regeneration method of the present invention, Fig. 2 is an explanatory diagram of the disadvantages when the amount of electrical discharge machining increases with short rolls, and Fig. 3 shows the above-mentioned disadvantages. 4 to 6 are side views or perspective views showing examples of application of the electrode tool to grindstones of various shapes; FIG. 7 is a perspective view of a curved electrode tool; FIG. 8 is a perspective view of a regeneration device applied to a grindstone having a complicated curved surface. 2, 15, 16, 20...metal bond grindstone,
4... Electrode tool, 6, 10, 21... Roll,
8, 12, 23, 27...Wire for discharge electrode.

Claims (1)

[Claims] 1. A wire support consisting of a roll or a template supports discharge electrode wires arranged in parallel at a certain pitch, and with these wire rows facing the working surface of a metal bond grinding wheel, the wires are cut from one end. At the same time as being fed out, the wires are rolled in from the other end while moving the wire rows relatively along the grinding wheel work surface in a direction that intersects with the direction of each wire, applying a voltage between the wires and the grinding wheel, A method for regenerating a metal bonded grindstone, characterized by performing discharge truing or discharge dressing of the grindstone by electric discharge between the two.