JPH0567377B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for machining a bearing guideway surface, and more specifically, the present invention relates to a method for machining a bearing guideway surface, and more specifically, it utilizes speed fluctuations of a linear motor to machining the machined surface of a workpiece by only grinding. The present invention relates to a bearing surface machining method in which unevenness is generated and elastohydrodynamic lubrication treatment is applied to the uneven surface.

[Prior Art] Conventionally, the method of machining a bearing guideway is to perform a normal grinding process on the machined surface of the workpiece, and then perform a process called "scraping" to improve the machined surface of the workpiece. The uneven surface was then subjected to elastohydrodynamic lubrication treatment.

[Problems to be Solved by the Invention] However, in the conventional bearing guideway machining method, the work is time consuming and requires a high level of skill. In addition, since the "scraping" process in particular is done by hand, the machined surface of the workpiece becomes an irregularly uneven surface, and the finishing accuracy due to elastohydrodynamic lubrication after the "scraping" process is also low.

The purpose of the present invention was proposed in order to solve the problem in view of the above circumstances, and it is an object of the present invention to machine a workpiece by only grinding by vibrating a table in a direction perpendicular to the feeding direction by varying the speed of a linear motor. The present invention provides a bearing guide surface machining method that produces unevenness on the surface and finishes it with high precision.

[Means for Solving the Problem] In order to achieve the above object, the present invention drives a table in a grinding machine with a linear motor, and moves the table in an orthogonal direction perpendicular to the feed direction by speed fluctuations in the feed rate of the table. The machine vibrates to grind the workpiece placed on the table.
Next, an elastohydrodynamic lubrication treatment is applied to the uneven surface formed on the machined surface of the workpiece.

[Operation] According to the present invention, when a table in a grinding machine is driven by a linear motor and grinding is performed on the machined surface of a workpiece, fluctuations in the table feed speed cause the table to move perpendicularly to the feed direction of the table. The table vibrates in the direction. If the table feed rate has a small variation, a narrow and shallow ground surface will result, and if the table feed rate has a large variation, a wide and deep ground surface will result. As a result, a larger uneven surface and a smaller uneven surface are generated on the machined surface of the workpiece, and then by applying elastohydrodynamic lubrication treatment to the uneven surface, the smaller uneven surface is scraped off to form a bearing guide surface. Can be finished with high precision.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a schematic front view of a surface grinder 1,
A table 5 is placed on the base 3, and the table 5 is moved in the left-right feeding direction as shown by the arrow in FIG. A magnetic chuck 7, which is a magnetic member for fixing the workpiece, is placed on the table 5, and the workpiece W is fixed onto the magnetic chuck 7. A grindstone 11 attached to a grindstone head 9 facing downward is rotated by a drive device (not shown), and a predetermined grinding process is performed on a workpiece W fixed on a magnetic chuck 7. Incidentally, the surface grinder 1 and the grindstone 11 are not particularly unusual, and may be ordinary ones that are conventionally used.

As shown in FIG.
It is guided by a guide surface 15 formed on the surface of the base 3 and moved in the left-right feeding direction in FIG.

As is clear from FIGS. 1 and 2, the table 5 in the surface grinding machine 1 is moved by the linear motor 13.
When grinding is performed on the workpiece W by driving with
Due to the fluctuation in the feed rate of the table 5, the table 5 vibrates in a direction orthogonal to the feed direction, causing an uneven surface on the machined surface of the workpiece W as shown in FIG.

As shown in FIG. 3, the uneven surface is composed of a larger uneven surface Wa and a smaller uneven surface Wb. The larger uneven surface Wa is caused by vibrations in the orthogonal direction (Y direction) orthogonal to the feed direction, which is the left-right direction (X direction) in FIG. 3, due to speed fluctuations in the feed speed of the table 5.

When the speed fluctuation of the feed rate of the table 5 is small, as shown in FIG.
becomes narrow and shallow, and when the speed fluctuation is large, the machined surface Wc of the workpiece W becomes wide and deep. The relationship between speed fluctuations and uneven surfaces on the machined surfaces Wc and Wd of the workpiece W is as shown in FIG. 4. Therefore, as the speed fluctuation of the feed rate of the table 5 increases, the uneven surface becomes larger.

The smaller uneven surface Wb is caused by torque fluctuations of the linear motor 13.

As a means of increasing the speed fluctuation of the feed speed of the table 5 mentioned above, in controlling the linear motor 13, etc., it is possible to cause a small speed fluctuation Vd in the maximum constant speed range of the speed command diagram shown in FIG. This is done by applying a loop. Further, mechanical means include, for example, in the case of a linear pulse motor, increasing the pitch and decreasing the gap to increase the torque fluctuation.

The above machining method produces the machined surface of the workpiece W as shown in Figure 3, but since it cannot be used as a bearing guide surface in that state, normal elastohydrodynamic lubrication is further performed to create a surface with smaller irregularities.
By removing Wb, the bearing guideway can be finished with high precision.

[Effects] As can be understood from the above description of the embodiments, according to the present invention, a table in a grinding machine is driven by a linear motor, and the table is moved perpendicular to the feed direction by speed fluctuations in the feed rate of the table. The workpiece placed on the table is vibrated in the perpendicular direction to grind the workpiece, and then elastohydrodynamic lubrication is applied to the uneven surface of the workpiece. Processing can be deleted. Therefore, the machining method of the present invention can shorten the working time, and even an unskilled worker can accurately machine the bearing guide surface. Furthermore, the uneven surface formed after the grinding process becomes more precise, and the effect of elastohydrodynamic lubrication can be enhanced, resulting in the effect that the bearing guide surface can be finished with high precision.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a surface grinder. Second
The figure is a partially sectional perspective view illustrating table feeding. FIG. 3 is an enlarged plan view of a workpiece processed by the processing method of the present invention. FIG. 4 is a diagram showing the relationship between the speed fluctuation of the table feed rate and the degree of unevenness on the machined surface of the workpiece. FIG. 5 is a speed command diagram of the linear motor. 1... Surface grinder, 5... Table, 7... Magnetic chuck, 11... Grinding wheel, 13... Linear motor.

Claims (1)

[Claims] 1. Driving a table in a grinding machine with a linear motor, vibrating the table in an orthogonal direction perpendicular to the feed direction due to speed fluctuations in the feed rate of the table, and grinding a workpiece placed on the table, A method for machining a bearing guide surface, the method comprising: then applying elastohydrodynamic lubrication to the uneven surface produced on the machining surface of the workpiece.