JPH0226606Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a grinding machine equipped with a tapered grindstone used for grinding a workpiece into a tapered shape, and particularly relates to improving the processing efficiency thereof.

[Prior art]

Conventionally, when grinding a workpiece into a tapered shape, a grinding machine with a grinding wheel shaft parallel to the tapered surface was used (for example, see Utility Model Application Publication No. 1546/1983), or a grinding machine with a grinding wheel that had the same taper shape as the surface to be machined was used. Grinding is performed using a grinding machine equipped with a grinding wheel (for example, see Japanese Utility Model Application Publication No. 1971-71285). For example, when processing the inner edge of a cylindrical workpiece into a tapered shape, In this state, the grindstone is rotated and the workpiece is rotated and moved in a direction perpendicular to its axis to grind the surface to be machined.

In addition, for a taper grindstone that reciprocates greatly in the axial direction, a workpiece with the axis of the taper hole parallel to the grindstone axis is synchronously moved orthogonally biaxially along a plane perpendicular to the grindstone axis. There is also a grinding machine that performs taper processing while drawing a three-dimensional Archimedean curve at a predetermined pitch in a tapered hole using the entire outer periphery of the grindstone (see, for example, Japanese Utility Model Application No. 81055/1983).

By the way, when grinding a workpiece, it is necessary to perform the grinding under conditions such as the circumferential speed of the grinding wheel, depending on the diameter of the workpiece surface, etc. Therefore, for the same workpiece, for example, even if the circumferential speed is Then it will be processed. On the other hand, the circumferential speed of a tapered whetstone is slower from the tapered surface to the tip, and faster toward the base. Therefore, when processing with this tapered whetstone, the circumferential speed of the tapered surface of the whetstone must be adjusted according to the above grinding conditions. Therefore, in the past, when mass producing the same workpiece, grinding was performed on a specific part of the tapered surface of the grinding wheel, and the number of parts processed on the workpiece was increased so that the part on the ground surface could not meet the dressing. When the required quantity was reached, the entire tapered surface of the grindstone was dressed.

[Purpose of invention]

The present invention has been made in view of the above-mentioned conventional situation, and aims to provide a grinding machine equipped with a tapered grindstone that can significantly improve machining efficiency and extend the life of the grindstone.

[Structure of the idea]

The present inventor believes that when mass producing the same workpiece using the conventional grinding machine described above, only a part of the grinding surface of the tapered grindstone is used, and if this part requires dressing, the entire grinding surface is dressed. This approach focused on the fact that dressing is required frequently, which lowers machining efficiency, and that areas that do not require dressing are also dressed, shortening the life of the grindstone. Therefore, in order to achieve the above-mentioned purpose, the present invention has developed a grinding machine equipped with a tapered grinding wheel, in which the effective grinding surface width of the grinding wheel is divided in the axial direction by a width corresponding to the width of the processed surface of the workpiece. A calculation circuit for calculating the number of grinding surface sections for calculation output, a counting circuit for outputting a grinding surface instruction signal for moving the grindstone section by section in accordance with a dressing completion signal for the grindstone and a predetermined number of machining completion signals for the workpiece, and a counting circuit for rotating and driving the grindstone. A grindstone drive device that moves the grindstone section by section in the direction of the grindstone axis based on the grinding surface instruction signal output from the grinding surface division number calculation circuit and the counting circuit; a workpiece drive device that moves the workpiece, and a grinding control device that controls both drive devices so that the workpiece is ground by each of the plurality of grinding surfaces formed by dividing the grindstone in the axial direction under grinding conditions according to the grinding surface. It is equipped with the following. That is, the workpiece is ground by each of the plurality of grinding surfaces formed by dividing the tapered surface of the grinding wheel in the axial direction, under grinding conditions corresponding to the grinding surface, and thereby the entire grinding surface of the grinding wheel is The number of workpieces that can be processed up to dressing can be increased by effectively using the grinding tool in grinding operations.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 5 are for explaining one embodiment of the present invention. In FIG. 1 showing the schematic structure, 1 is a bed, and a whetstone table 2 is shown on the upper surface of the bed 1. A ball screw 3 for moving the grindstone table is screwed into a female screw box (not shown) which is placed slidably in the left and right direction and is fixed to the lower surface of the grindstone table 2, and its output shaft is connected to the ball screw 3. A grindstone section moving motor 4 is fixed to the bed 1. A wheel head motor 5 is mounted on the grindstone table 2, and a tapered grindstone 6 is connected to the output shaft of the motor 5. The grindstone table 2, each motor 4, 5, etc. A grindstone drive device 7 is configured to rotationally drive the grindstone and reciprocate in its axial direction.

In addition, on the left side of the upper surface of the bed 1 as shown in the figure,
A work table 8 is placed so as to be slidable in the vertical direction in the figure, and a ball screw 9 for moving the work table in a cut is screwed into a female screw box (not shown) fixed to the lower surface of the work table 8. A work table cutting movement motor 10 having an output shaft connected to the work table is fixed to the bed 1. Further, a headstock 11 for chucking the work W is mounted on the work table 8,
A drive motor 12 is mounted near the headstock 11 of the work table 8, and a drive belt 13 is wound between a drive pulley 12a fixed to the output shaft of the motor 12 and a driven pulley 11a of the headstock 11. This constitutes a workpiece driving device 14 that rotates the workpiece W and reciprocates it in a direction perpendicular to its axis.

Further, a grindstone dressing device 15 is attached to the work table 8, and this is of a swinging type, and its swinging arm 15a is attached to the drive unit 1.
5b, and a dressing tool 15c is attached to the swing arm 15a.

Control signals S2, S1, and S3 from a grinding control device 16 are input to each of the motors 4, 5, and 10, and the grinding control device 16 includes a grinding surface segment number calculation circuit 17, a counting circuit 18, and a grinding wheel control device. It is composed of a circuit 19 and a workpiece control circuit 20.

The grinding surface division number calculation circuit 17 is for calculating and outputting the number N of grinding surfaces that can divide the effective grinding surface width of the grinding wheel 6 into widths corresponding to the width of the workpiece surface of the workpiece W in the axial direction. (See Figure 2), the processed surface of the workpiece W
Unit grinding surface width setting section 17 for setting the unit grinding surface width l of the grindstone necessary for grinding the width lo of Wa
a, an effective grinding surface width setting section 17b for setting the effective grinding surface width L of the grindstone 6, and the above set values l, L.
A grinding surface section number calculating section 17c calculates the number of grinding surface sections N (=L/l) from the following (decimal points are rounded down). Here, N represents the number of grinding surface sections as well as the grinding surface number; in the example of FIG.
corresponds to

The counting circuit 18 is for outputting a grinding surface instruction signal So for instructing the grinding surface of the grinding wheel 6 to be processed, and when a dressing signal indicating that the grinding wheel 6 has been dressed is inputted, the Output the grinding surface number A corresponding to the number of divisions N,
When the number of processing completion signals indicating the completion of grinding of one workpiece W reaches the number of workpiece processing set for each grinding surface, grinding surface numbers B, C, . . . are sequentially output.

The grindstone control circuit 19 controls the grindstone 6 to the grinding surface A,
The grinding wheel 6 is driven to rotate at a rotational speed corresponding to B and C, and the grinding surface of the grinding wheel 6 is the workpiece surface of the workpiece W.
This is for moving in the axial direction according to the machining movement amount for positioning at Wa, and consists of a wheel head motor control circuit and a grindstone section movement motor control circuit. The wheel head motor control circuit includes a wheel head motor rotation speed setting circuit 19a that reads out the rotation speed corresponding to the grinding surfaces A, B, and C from the wheel head motor rotation speed map shown in FIG. The wheel head motor drive circuit 19b outputs the drive signal S1 to the wheel head motor 5, and the grindstone segment movement motor control circuit controls the machining movement that calculates and outputs the grindstone position according to the grinding surfaces A, B, and C. Quantity calculation circuit 1
9c, and a grindstone segment movement motor drive circuit 19d that outputs a drive signal S2 to the grindstone segment movement motor 4 to obtain this movement amount.

The workpiece control circuit 20 is for moving the workpiece W in the direction of the perpendicular axis at cutting speeds corresponding to the grinding surfaces A to C. This is based on the cutting speed map shown in FIG. A cutting speed setting circuit 20a that reads cutting speeds corresponding to surfaces A to C, and a work table cutting movement motor drive circuit that outputs a drive signal S3 for obtaining this cutting speed to the work table cutting movement motor 10. 20b.

Next, the operation will be explained using FIGS. 1 to 5.

In this embodiment, the number of grinding surface sections N is 3, and the number of workpieces that can be machined on each grinding surface A, B, and C is n1.
This will be explained as n2 and n3.

When the workpiece W is loaded onto the headstock 11 and the unit grinding surface width l and the effective grinding surface width L are set, the grinding surface section number calculation circuit 17c calculates N (=L/l).
=3 is calculated and output, and when the dressing signal is input to the counting circuit 18, the circuit 18 outputs the grinding surface number A corresponding to the grinding surface division number 3 to the grinding wheel control circuit 19 and the workpiece control circuit 20. . Then, the wheel head motor rotation speed m1 corresponding to the grinding surface A is read from the wheel head motor rotation speed map, and a control signal S1 for obtaining the above rotation speed m1 is output from the wheel head motor drive circuit 19b to the wheel head motor 5. is,
At the same time, the processing movement amount calculation circuit 19c calculates and outputs the grinding wheel movement amount for making the grinding surface A correspond to the processed surface Wa of the workpiece W, and obtains the movement amount from the grinding wheel classification movement motor drive circuit 19d. The control signal S2 of the grinding wheel section movement motor 4
is output to. In addition, the cutting speed setting circuit 20
At step a, the cutting speed v1 corresponding to the grinding surface A is read from the cutting speed map, and the cutting speed v1 corresponding to the grinding surface A is read out from the cutting speed map, and the cutting speed
A control signal S3 for obtaining v1 is output to the work table cutting movement motor 10. As a result, the grindstone 6 is rotated by the wheel head motor 5 at the rotational speed m1, and is advanced by the grindstone section movement motor 4 until the grinding surface A is located on the workpiece surface Wa of the workpiece W. The loading is completed (see Figures 5a and b). When this grindstone indexing is completed, the workpiece W is rotationally driven by the drive motor 12 and moved in the axis-perpendicular direction by the worktable cutting movement motor 10 at the cutting speed v1 (see Fig. 5c). .

When the workpiece surface Wa of the workpiece W reaches a predetermined inner diameter dimension, the cutting feed ends, and the workpiece W
is retracted to its original position, and the grinding wheel 6 is also retracted to its original position (see FIGS. 5d and 5e), and at this time, a machining completion signal is input to the counting circuit 18.

When the machining of the first workpiece W is completed,
This is unloaded, and the next workpiece W is loaded and sequentially processed in the same manner as above. When the number of machining completion signals reaches the number n1 of workpieces that can be machined on the grinding surface A, the counting circuit 18
A grinding surface number B corresponding to the number of grinding surface divisions 2 (=N-1) is output from. Then, the wheel head motor control circuit outputs a control signal S1 to obtain the motor rotation speed m2 corresponding to the grinding surface B, and the grinding wheel section movement motor control circuit obtains the amount of movement of the grinding surface B to be located on the workpiece surface Wa. control signal S for
2 is output, and a control signal S3 for obtaining a cutting speed v2 corresponding to the grinding surface B is outputted from the workpiece control circuit 20, whereby the grinding wheel is adjusted so that the grinding surface B is positioned on the workpiece surface Wa of the workpiece W. Indexing is performed (see Figures 5 f and g), and then grinding is performed at the cutting speed v2 (see Figure 5 h).
reference).

When the number of processing completion signals reaches n1+n2,
The grinding surface number C is output from the counting circuit 18, and the workpiece W is ground by the grinding surface C in the same manner as described above. And the number of workpiece machining completion signals is n1 + n2 + n3
When this point is reached, dressing of the grindstone 6 is performed. In this case, the swinging arm 1 of the dressing device
5a is in a substantially horizontal state, and in this state, the grindstone table 2 and work table 8 move forward,
The grindstone 6 is driven to rotate, thereby shaping the entire grinding surface of the grindstone 6 into a tapered shape. When this is completed, a dressing signal is input to the counting circuit 18, and the circuit 18 outputs the grinding surface number A again.

In this embodiment, the grinding wheel 6 is divided into a plurality of grinding surfaces A to C in the axial direction, and the machining conditions are set according to each grinding surface, for example, the number of rotations of the grinding wheel m1 to m3, the cutting speed v1
Even in ~v3, process a predetermined number of workpieces n1 to n3,
In addition, since the entire ground surface is dressed at the same time when all the ground surfaces A to C require dressing, the number of workpieces that can be processed in one dressing operation can be increased and processing efficiency can be greatly improved. Further, unlike the conventional method, it is not necessary to grind one part of the whetstone and then dress the other part, and as a result, the life of the whetstone can be extended.

In the above embodiment, a case has been described in which the grinding surface of the grindstone 6 is divided into three sections, but of course the number of sections is not limited to three, and the workpiece W
The width of the processed surface Wa, the size of the grindstone b, etc. are selected as appropriate. In addition, in the above embodiment, the grinding conditions were explained using an example in which the rotational speed of the grindstone and the cutting speed were changed for each grinding surface.
Various other grinding conditions may be considered.For example, the cutting speed may be changed as the number of workpieces increases, since the sharpness of the grinding surface decreases as the number of workpieces increases. .

Furthermore, although the above embodiment describes the case where the inner surface of the workpiece is ground, the present invention can also be applied to the case where the outer surface of the workpiece is ground.

Furthermore, although the present invention relates to a grinding machine equipped with a tapered type grinding wheel, the idea of dividing the grinding surface of the grinding wheel in the axial direction is based on the idea that a cylindrical grinding wheel can be used to cut the inner or outer surface of a cylindrical workpiece. It can also be applied to grinding.

[Effect of idea]

As described above, according to the grinding machine equipped with the tapered grindstone according to the present invention, the grinding surface of the grinding wheel is divided into a plurality of sections in the axial direction, and grinding is performed under grinding conditions according to each grinding surface. This has the effect of increasing the number of workpieces that can be processed with one dressing of the grindstone, greatly improving processing efficiency, and also has the effect of reducing the number of dressings of the grindstone, thereby extending the life of the grindstone.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a grinding machine equipped with a tapered grindstone according to an embodiment of the present invention, Fig. 2 is a diagram for explaining the number of grinding surface sections, and Fig. 3 is a diagram showing the grinding surface and the wheel head motor. Diagram showing the relationship with rotation speed,
FIG. 4 is a diagram showing the relationship between the grinding surface and the cutting speed, and FIGS. 5 a to 5 h are diagrams for explaining the operation. 6... Grinding wheel, 7... Grinding wheel drive device, 14... Work drive device, 16... Grinding control device, A to C...
...Grinding surface, W...Work.

Claims (1)

[Scope of Claim for Utility Model Registration] In a grinding machine equipped with a tapered grindstone for grinding the tapered surface of a workpiece, the effective grinding surface width of the grindstone is divided in the axial direction by a width corresponding to the width of the processed surface of the workpiece. a grinding surface section number calculation circuit that calculates and outputs the number of grinding surfaces that have been ground, and a counting circuit that outputs a grinding surface instruction signal that moves the grindstone section by section according to the dressing completion signal of the grindstone and the machining completion signal of a predetermined number of workpieces; a grindstone drive device that rotationally drives the tapered grindstone and moves the grindstone section by section in the direction of the grindstone axis based on the grinding surface instruction signal output from the grinding surface division number calculation circuit and the counting circuit; and a grindstone drive device which rotationally drives the workpiece. and a work drive device that moves the work in a direction perpendicular to the axis of the work, and a workpiece that is ground by each of the plurality of grinding surfaces formed by dividing the grindstone in the axial direction under grinding conditions according to the grinding surface. A grinding machine equipped with a tapered grindstone, characterized in that it is equipped with a grinding control device that controls both of the above drive devices.