JPH0367825B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method of grinding a cylindrical surface and end surface of a workpiece using an angular grindstone.

<Prior art> In general, in grinding using an angular grindstone that has a cylindrical surface and an end surface that form an acute angle with respect to the axis of rotation of the grindstone, plunge cut grinding that simultaneously grinds the cylindrical portion and end surface, and plunge cut grinding that grinds the cylindrical portion and the end surface at the same time, When the grinder is wide, there are traverse grinding, in which the cylindrical part is ground by traversing the table, and oscillation grinding, which is used to improve surface accuracy after plunge grinding.The cylindrical part and end face are usually ground in separate processes.
In grinding the cylindrical surface and grinding the end face using these separate processes, the grindstone is fed into the cylindrical part to the finished dimension and traverse-grounded, then the end face is cut and ground, and the finished dimension is also achieved in the radial direction. I'm sending it to you. In this case, as shown in Fig. 7, the amount of deflection of the workpiece during cylindrical part grinding is different from the amount of deflection of the workpiece during end face grinding, so the grindstone locally contacts the previously finished cylindrical surface. As a result, the edges of the grindstone may cause streaks on the workpiece, resulting in poor finishing accuracy in those areas.

Conversely, if the end face is first ground to the finished dimension and then the cylindrical part is traversed to a position where it contacts the previously finished end face, the amount of deflection of the workpiece can be reduced. Due to the difference, the grinding wheel and the end face come into local contact, resulting in deterioration of the accuracy of the end face.

<Problems to be Solved by the Invention> In this way, either the cylindrical surface or the end surface is first ground to the finished dimension, and when grinding the remaining end surface or cylindrical surface, the grinding surface that has already been finished is When the whetstone is fed relatively to the point where it makes contact,
Since the grinding wheel and the finished surface are locally contacted and ground, there is a problem in that the cylindricity of the cylindrical surface or the flatness of the end surface is deteriorated.

<Means for Solving the Problems> In order to eliminate such problems in the conventional art, the present invention has been developed by grinding either the cylindrical surface or the end surface to the finished dimension, and then grinding the remaining end surface or the cylindrical surface with a grindstone. The grinding process is performed by cutting and grinding, and the cutting is stopped by leaving a gap with respect to the already finished machined surface.

<Function> Since cutting is stopped with a gap on the machined surface that has already been ground to the finishing dimension, the amount of deflection of the workpiece during cylindrical surface processing and the deflection of the workpiece during end face processing is reduced. Even if there is a difference in the amount, local contact between the grinding wheel and the already finished grinding surface can be prevented, and the precision of the machined surface will not deteriorate.

<Examples> Examples of the present invention will be described below based on the drawings. FIG. 1 shows the configuration of an interactive CNC grinding machine, in which a grinding wheel head 12 and a table 11 are guided orthogonally, an Aguilar grinding wheel 12a is mounted on the grinding wheel head 12, and a headstock 17 is mounted on the table 11. and tailstock 1
8 have been adjudicated. Grindstone head 12 and table 1
1 are screwed with feed screws 13 and 14, respectively,
It is also drivingly connected to servo motors 15 and 16. Servo motors 15, 16 drive rotation 27, 2
8 and is controlled by command pulses given from the numerical control device 20. Numerical control device 20
A manual pulse generator 21, a CRT 22, and a keyboard 25 are connected to the , and the grinding operation can be performed by setting the table 11 in advance so that the grinding program can be entered in an interactive manner as shown in the cycle diagram described later. By positioning the wheel head 12 at a predetermined position and moving the wheel head 12 forward, the cylindrical surface of the workpiece supported by the headstock 17 and the tailstock 18 can be ground. If the table 11 is moved in the direction of the grindstone after the table 11 has been advanced to the point where the workpiece is moved forward, the end face of the workpiece can be ground.Furthermore, if the advancement of the grindstone head 12 and the movement of the table 11 are simultaneously controlled using two axes, the angular Whetstone 1
2a allows simultaneous plunge grinding of the cylindrical surface and end surface of the workpiece.

A Plunge Grinding Figure 2 shows the state of plunge grinding of the cylindrical part and the end face. As mentioned above, simultaneous two-axis feed control of the grindstone head 12 and table 11 allows synthetic feed in the direction of the arrow. Grinding is done. Figure 3 shows one example of such plunge grinding.
As an example, a grinding cycle diagram is shown in which oscillation grinding is performed on a cylindrical portion after plunge grinding is completed. Plunge grinding in the angular direction consists of rapid traverse 1 of the grinding wheel alone, dry grinding 2 with combined feed, rough grinding 3, fine grinding 4, fine grinding 5, and gradually grinding wheel 1.
The cutting speed 2a is reduced, and at the final cutting end of fine grinding 5, the cylindrical surface and end surface of the workpiece are finished to the finished dimensions. In the subsequent oscillation grinding 6, the table 11 is moved in the direction in which the end face of the workpiece is separated from the grinding wheel by l minutes, while keeping the radial depth of cut at zero, and the direction is changed to l-
After that, repeat the oscillation of the stroke la several times. In this way, in oscillation grinding after plunge grinding the cylindrical surface and the facing surface at the same time, by performing oscillation grinding with a gap of a left for the end surface that has been finished to the final dimensions, the end surface that has been finish ground can be Deterioration of surface accuracy can be prevented. Note that the gap a may be approximately 0.02 to 0.1 mm. FIG. 4 shows another example of plunge grinding, in which plunge grinding of only the end face and oscillation finish grinding of the end face are added to the cycle described above. Plunge grinding in the angular direction is the same as described above, including rapid traverse 1, dry grinding 2, and rough grinding 3, and then plunge grinding 4 of the end face.
→ 5 → 6 → 7 → 8 → 9 are performed, and then intermediate finishing 10 of the end face is performed. Fine grinding 11 and fine grinding 12 are performed again as plunge grinding in the angular direction, and oscillation grinding 13 of the cylindrical portion is performed with a gap a left between the plunge-ground end face in the same manner as in the previous example. Thereafter, the end face is subjected to oscillation grinding 14 to give a final finish to the end face. In such oscillation grinding of the end face, oscillation grinding is also performed with a gap of a certain amount b remaining in the cylindrical surface that has already been finished.

B Traverse Grinding Figure 5 shows the state of traverse grinding of the cylindrical part of a long workpiece. In order to grind a cylindrical surface wider than the width of the grinding wheel, the table is traversed over the length of the cylindrical part of the workpiece. FIG. 6 shows, as an example of such traverse grinding, a grinding cycle diagram in which rough cutting of a cylindrical portion is performed by plunge grinding, and then the cylindrical portion is finished by traverse grinding.

Plunge grinding, which removes most of the machining allowance of the cylindrical portion, is performed by repeating the cycle of rapid feed 1, dry grinding 2, rough grinding 3, and return 4 several times at a predetermined position in the axial direction of the workpiece. In this case, at the plunge grinding cut end at the position closest to the end face of the workpiece, the grindstone may cut into the end face by a predetermined amount, or it may be established so that a slight gap is maintained. After empty grinding 14 and rough grinding 15, which are the final stages of plunge grinding, the table 11 is moved 16, the end face of the workpiece is brought into contact with the end face of the grinding wheel, the cut is made to the finishing dimension 17, and then the grinding wheel is released. Then, change the radial position 18, 19, make a depth of cut 20 against the end face, perform plunge grinding on the end face, and move the grindstone radially with the depth of cut 0.
1 to perform semi-finishing of the end face. From this point, the table is offset by a certain amount C with respect to the end face, and traverse grinding 22, 23, . . . 34 of the plunge-ground cylindrical surface is performed. In the illustrated example, the left and right traverse ends are both-end cuts that make a cut every time, but it is also possible to make a single-sided cut that makes a cut only at one traverse end, and in either case, the traverse end on the end face side is
A gap by an offset amount C is left from the end face. The final stage of traverse grinding is completed by performing spark-out grinding 35. A grindstone is brought into contact with the end surface from a position spaced apart by a certain amount d from the lowered cylindrical surface and moved in the radial direction to perform oscillation grinding 36 of the end surface. The above-mentioned gaps b, c, and d are set to values in the same range of 0.02 to 0.1 mm as a, and may be determined as appropriate depending on the shape of the workpiece and the grinding conditions.

<Effects of the Invention> As explained above using the cycle diagrams, regardless of plasin grinding, traverse grinding, or oscillation grinding, when either the end face or the cylindrical face is finished first, the other face is finished. When grinding, by leaving a certain gap on the finished surface, you can prevent the grinding wheel from hitting the previously finished surface locally and causing streaks, etc., and improve the accuracy of the machined surface. This has the advantage of being able to prevent a decline in

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG.
The overall configuration of the CNC grinding machine. Figure 2 is a diagram showing the plunge grinding state, Figures 3 and 4 are cycle diagrams mainly for plunge grinding, Figure 5 is a diagram showing the traverse grinding state, and Figure 6 is a diagram showing the plunge grinding state. The figure is a cycle diagram mainly for traverse grinding, and FIG. 7 is an explanatory diagram showing the causes of conventional problems. 11...Table, 12...Whetstone stand, 17...
Headstock, 18... tailstock, 15, 16... servo motor, 20... numerical control device.

Claims (1)

[Claims] 1. Grind either the cylindrical surface or the end surface of the workpiece by cutting into the workpiece with an angular grindstone having a cylindrical surface parallel to the workpiece axis and an end surface perpendicular to this on the outer circumference of the grindstone, and then A grinding method for grinding the other side, which involves cutting the cylindrical surface or end surface to the finished dimension and finishing grinding, and then cutting the remaining end surface or cylindrical surface that has not been ground to the finished dimension with a grinding wheel. A grinding method using an anguilla grindstone, characterized in that cutting is stopped with a gap provided to an already finished machined surface.