JPH0947951A - Grinding machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent vibration generated by the influence of a groove formed by preceding machining of a grinding wheel by fluctuating the pitch of a groove at each processing. SOLUTION: When cutting is applied on a work a plurality of times, the pitch of a groove occurring due to machining is fluctuated at each machining. Namely, Machining is effected in such a state that the pitch of a present groove Ib is changed from that of a preceding groove Ia. In this constitution, a part shown by an oblique line is a part to be removed and in this case, the machining pitch of the present groove Ib is differed from that of the preceding groove Ia, no regularity of vertical movement of a grinding wheel II is produced and the generation of vibration is reduced. This constitution reduces the generation of vibration of the grinding wheel and prevents worsening of roughness of a machined surface owing to vibration of the grinding wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding method suitable for grinding an axially symmetrical object (workpiece) such as a glass press lens, a plastic lens mold, an aspherical mirror, and an aspherical lens. .

[0002]

2. Description of the Related Art FIG. 3 is a main part configuration diagram for explaining an example of a grinding apparatus used for carrying out the present invention.
I is a work piece, II is a grindstone, and as is well known, the corner of the grindstone II.
IIa is applied to the workpiece I, and the workpiece I is rotated to grind the surface of the workpiece.

FIG. 4 is an enlarged view showing a state of a contact point between the grindstone II and the workpiece I. As shown in the figure, a corner IIa of the grindstone II is shown.
Thus, the groove Ia is formed in the workpiece I.

[0004]

FIG. 5 is a partially enlarged view showing a state in which the grooves Ia are processed with the same cycle, in which A is a groove formed by the previous processing and B is a new one. A groove is shown, and a hatched portion shows a portion removed by processing. In this way, if the grooves are machined with the same cycle, the corner of Grindstone II
As indicated by arrow C, IIa regularly moves up and down to generate vibration.

As described above, in the grinding method using the corners of the grindstone, when the processing is performed a plurality of times, if the processing is continued without changing the pitch of the grooves generated by the processing, a new cut is given. At this time, a phenomenon occurs in which the grindstone vibrates up and down due to the influence of the groove formed by the previous machining, and the roughness of the machined surface deteriorates. The present invention has been made in view of the above circumstances, and an object thereof is to suppress the occurrence of vibration by changing the pitch of the grooves generated by the grindstone for each processing. Another object of the present invention is to improve the surface roughness of the machined surface by performing the machining without making a new cut and making the pitch of the groove generated by the machining narrower than the previous machining.

[0006]

According to a first aspect of the present invention, in a grinding method for grinding a workpiece by applying a corner of a grindstone to the workpiece, a plurality of cuts are made in the workpiece. The pitch of the grooves generated by the processing is changed for each processing, so that the whetstone is prevented from vibrating under the influence of the grooves formed by the processing performed last time.

According to a second aspect of the present invention, in a grinding method in which a corner of a grindstone is applied to a rotary processed product to grind the processed product, the processed product is formed by machining without making a new cut. By making the groove pitch narrower than the previous processing and performing the processing a plurality of times, a processed surface having a better surface roughness can be obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an enlarged view of an essential part for explaining an embodiment of the invention of claim 1, in which I is a workpiece,
II is a grindstone, and in this embodiment, in the grinding method of grinding the workpiece by bringing the corners of the grindstone into contact with the rotating workpiece, when a plurality of incisions are given to the workpiece, a groove generated by the machining The pitch of No. 4 is changed for each processing, and the grindstone is prevented from vibrating under the influence of the groove generated by the previous processing.
Indicates a groove formed by the previous processing, B indicates a groove that can be newly formed, and shows a state in which the groove Ib of this time is changed from the pitch of the groove Ia of the previous time and processing is performed. In the case of FIG. 1 as well, as in the case of FIG. 5, the shaded portion is the portion to be removed. In this case, the machining pitch of the groove Ib at this time is the same as the groove I at the previous time.
This is different from the machining pitch of a, and compared to the case shown in FIG. 5, the vertical movement of the grindstone II has no regularity and vibration is reduced.

FIG. 2 is an enlarged view of an essential part for explaining an embodiment of the invention of claim 2. In this embodiment, a rotary work piece is brought into contact with a corner portion of a grindstone to grind the work piece. In the grinding method to do, without giving a new cut to the workpiece,
It is characterized in that the pitch of the groove generated by the processing is made narrower than that of the previous processing and the processing is performed a plurality of times to obtain a processed surface having a better surface roughness. As a result, as shown in FIG. Groove I without making a new cut
Machining was performed by sequentially narrowing the pitches of a, Ib, and Ic. FIG. 2A shows the first machined surface, FIG. 2B shows the second machined surface, and FIG. The processed surface of the second time is shown. In this case, compared to the case of processing at the same pitch,
The uncut portion is reduced and the surface roughness is improved.

As described above, in the grinding method of the present invention, when the workpiece is cut a plurality of times, the pitch of the grooves generated by the processing is changed for each processing,
Alternatively, the pitch of the groove formed by the processing is made narrower than that of the previous processing to perform the processing a plurality of times without giving a new cut to the workpiece. , It is better to change the rotation speed of the workpiece,
In that case, the number of rotations of the workpiece is 100 to 50 at the time of the previous processing.
It is recommended to set it to 0%. Also, to change the processing conditions,
It is advisable to change the feed rate of the grindstone, and in that case, the feed rate of the grindstone may be set to 100 to 500% of the previous processing.

[0011]

According to the invention of claim 1, since the pitch of the groove generated by the angle of the grindstone is changed for each machining, the vibration of the grindstone is reduced, and the roughness of the machined surface is deteriorated by the vibration of the grindstone. Can be prevented. According to the second aspect of the present invention, since the machining is performed by narrowing the pitch of the grooves generated by the machining without giving a new cutting, the uncut portion is reduced and the surface roughness of the machined surface is improved.

[Brief description of drawings]

FIG. 1 is an enlarged view of an essential part for explaining an embodiment of the invention of claim 1;

FIG. 2 is an enlarged view of an essential part for explaining an embodiment of the invention of claim 2;

FIG. 3 is a configuration diagram of a main part for explaining an example of a grinding apparatus used for carrying out the present invention.

FIG. 4 is an enlarged view showing a state of a contact point between a workpiece and a grindstone in the grinding apparatus shown in FIG.

FIG. 5 is a diagram for explaining an example of a conventional processing method when processing is performed with the same groove cycle.

[Explanation of symbols]

1 ... Workpiece, Ia, Ib, Ic ... Groove, II ... Whetstone, IIa ...
The corner of the whetstone.

Claims (2)

[Claims] 1. In a grinding method in which a corner of a grindstone is brought into contact with a rotary workpiece to grind the workpiece, when a plurality of incisions are made in the workpiece, the pitch of grooves generated by the machining is set for each machining. The grinding method is characterized in that the whetstone is prevented from vibrating under the influence of the groove generated by the previous processing. 2. A grinding method in which a corner of a grindstone is brought into contact with a rotary processed product to grind the processed product, and the pitch of grooves generated by the machining is previously set without giving a new cut to the processed product. The grinding method is characterized by obtaining a machined surface with a better surface roughness by performing the process several times with a narrower width than the process of.