JPH07164314A - Grinding wheel dimension measuring method and device in grinding machine - Google Patents

Abstract

PURPOSE:To eliminate working errors caused by visual observation for the measurement of a grinding wheel shape, enable highly accurate working, and concurrently enable unmanned working for a long period of time. CONSTITUTION:In the grinding machine 1 equipped with a grinding wheel head 11 pivotally supporting a grinding wheel spindle shaft 2 mounted with grinding wheel 9 for grinding a work in such a way as to be freely rotated, a molded grinding wheel rotating means 29 is provided, which has a molded grinding wheel 35 installed on a rotating shaft 31 provided for a table 21 having the work rested, also having a axial center perpendicularly intersected with the grinding wheel spindle shaft 27. Furthermore, a sensor 43 for measuring the outer diameter of the molded grinding wheel 35 and a sensor 35 for detecting the contact of a grinding wheel are provided for a molded grinding wheel rotating means 29, and a control means 3 is provided, which can measure the grinding wheel 9 based on the detection made by the sensors 43 and 39, and is equipped with a molding cycle program forming means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grindstone size measuring method and apparatus for a grinding machine.

[0002]

2. Description of the Related Art Conventionally, for example, the tip shape of a superabrasive grindstone used for a forming grinder is usually formed in a true arc shape for grinding a complicated contour shape. The NC forming grinder controls the locus of the center point of the arc, and the tip shape of the grindstone is magnified by a projector and visually measured.

More specifically, referring to FIG. 8, FIG. 9 and FIG. 10, FIG. 8 shows the entire screen, and the projector screen 101 has a work 103, a grindstone 105 and A.
A concentric circle 107 indicated by a part is filled in. Next, as shown in FIG. 9, a dummy 109 for measuring the tip diameter of the grindstone 105 is set on the lateral center axis of the concentric circle. The material of the dummy 109 is generally a thin plate such as carbon or iron, and can be easily shaved without breaking the shape of the grindstone.

Then, the grindstone 105 is directed toward the concentric circle 107 in the Y direction to grind the dummy 109. At this time, the X and Y coordinates of the wheel head are recorded (see FIG. 9).

Concentric circle 1 with the arc of the processed dummy 109
Move the table so that it matches 07. Then, when the circular arc of the dummy 109 and the concentric circle 107 substantially coincide with each other, the movement amount of the table X and Y axes is added to and subtracted from the previously recorded X and Y coordinates of the grinding wheel head (center of the concentric circle) = (Center of the whetstone tip R)
The center coordinate of is calculated. Further, the radius R of the grindstone tip can also be read by matching the circular arc of the dummy 109 with the concentric circle 107.

Further, there is a means, which is adopted in Japanese Patent Publication No. 4-71667, for calculating the arc radius and the arc center position by detecting the predetermined three points at the tip of the grindstone.

[0007]

By the way, in the above-mentioned conventional grindstone dimension measuring means in the grinding machine, since the tip shape of the grindstone is visually confirmed, it is not possible to grasp the exact arc radius or the arc center point, and therefore the grindstone tip. There is a problem that a processing error occurs due to a point alignment error.

More specifically, in the measuring means described with reference to FIGS. 8 to 10, when the dummy 109 and the concentric circle 107 are aligned with each other, or when the tip R diameter of the grindstone 105 is measured,
Accurate measurement in the unit of several μm is impossible.

Therefore, the finishing work is not performed immediately at the time of working, and the work is once processed by including the intermediate finishing process. After machining, the center position is corrected and the tip of the grindstone R is checked by observing the remaining finishing allowance of the work and the amount scraped during the intermediate finishing.
The final correction was done by changing the diameter correction.

For this reason, one step of intermediate finishing is required before finishing, and it takes a lot of processing time for the whole machining. The machining allowance of the workpiece after the intermediate finishing is visually confirmed, and the R center position of the tip of the grindstone is confirmed. Since the correction and the change in the R diameter correction amount are performed, a visual measurement error at that time will occur as a processing error.

Further, the means for calculating the arc radius and the arc center position known in Japanese Patent Publication No. 4-71667 only detect at three points, so it is not known whether the tip end is an arc shape or not. Further, if the circular arc is not a perfect circle, the inconvenience arises in that it is calculated by shifting to the central position of the circular arc.

In order to improve the above-mentioned problems, an object of the present invention is to eliminate the processing error caused by the visual measurement of the grindstone shape, enable high-precision processing, and enable unmanned processing for a long time. It is an object of the present invention to provide a method for measuring a grindstone size on a board and an apparatus therefor.

[0013]

In order to achieve the above object, the present invention provides a grinder having a grindstone head rotatably supporting a grindstone spindle shaft equipped with a grindstone for grinding a work, The grindstone spindle axis is rotated while moving in the up-down direction, and a grinding wheel having an axis perpendicular to the grindstone spindle axis is brought into contact with the grindstone to move the grindstone in an arc around the shaping grindstone, and the radius of the shaping grindstone , A grinding wheel size measuring method in a grinding machine for detecting the contact between the grinding wheel and the forming grinding wheel to detect the arc size and the arc center position of the grinding wheel tip while performing truing and dressing.

Further, the present invention is a grinding machine equipped with a grindstone head rotatably supporting a grindstone spindle shaft on which a grindstone for grinding a work is mounted, the grinder being provided on a table for mounting the work, and Provided is a forming wheel rotating device having a forming wheel attached to a rotary shaft having an axis orthogonal to the wheel spindle axis, and this forming wheel rotating device is provided with a sensor for measuring the outer diameter of the forming wheel and a sensor for detecting the contact of the wheel.
A control device equipped with means for measuring a grindstone and forming cycle program by means of the detection of each of the above-mentioned sensors, and a grindstone dimension measuring device in a grinder are configured.

[0015]

By employing the method and apparatus for measuring the grindstone in the grinding machine of the present invention, the grindstone spindle shaft having the grindstone mounted thereon is rotated while being moved in the vertical direction, so that the axis of the grindstone surface is perpendicular to the spindle axis. The shaped grindstone provided in the shaped grindstone rotating device is brought into contact. Then, the contact is detected by the grindstone contact detection sensor, the grindstone is moved in an arc around the forming grindstone, the detection value and the tooling condition of the forming grindstone diameter measuring sensor and the grindstone contact detecting sensor, and the dressing condition. And the like are input to the grindstone measuring / forming cycle program creating means, and the output of the forming / measuring cycle program creating means is fetched into the control device to form the grindstone.

[0016]

Embodiments of the present invention will be described in detail below with reference to the drawings. Although an optical profile grinding machine will be described as the grinding machine, the grinding machine is not limited to this model. Further, since the structure of the optical profile grinding machine is already known, detailed illustration and description thereof will be omitted.

Referring to FIG. 1, an optical copying grinding machine 1 as a grinding machine is provided with an operation panel (not shown) for inputting and outputting machining information especially to a storage device. This operation panel is provided with a frame 5 accommodating a storage device and an NC device 3 as a control device for the grinding machine based on the storage device.

The optical copying grinding machine 1 is provided with a column 13 supporting a grindstone head 11 for holding a disk-shaped grindstone 9, for example, on the upper left side of a base 7, and the grindstone 9 is rotatable and the grindstone head is provided. It is provided so as to be vertically movable along the Z-axis direction (vertical direction in FIG. 1). A drive unit 15 for rotating the grindstone 9 via a belt or the like by a drive means such as an electric motor is provided on the back surface of the column 13.

The column 13 has a pedestal 17 on its lower surface,
Along the guide groove (not shown) formed on the upper surface of the cradle 17,
It moves in the X-axis direction (front-back direction in FIG. 1).

On the lower surface of the pedestal 17, there is provided a movable base 19 for moving the column 13 having the grindstone 9 and the grindstone head 11 in the X-axis direction. Y-axis moving means (not shown) for moving the column 13 in the Y-axis direction (the left-right direction in FIG. 1) is provided on the lower surface.

A table 21 for holding a workpiece is provided at a position facing the grindstone 9 on the right side of the upper surface of the base 7, and the table 21 is moved along the guide surface of the X-axis moving table 23 provided on the lower surface in the X direction. It is movable in the axial direction.

A Y-axis moving table 25 having a guide surface movable in the Y-axis direction is provided on the lower surface of the X-axis moving table 23.
The Y-axis moving table 25 is moved by the driving means (not shown) to Y
It is movable in the axial direction. In addition, the Y-axis moving table 25
Is movable in the Z-axis direction and is moved up and down by Z-axis drive means (not shown) such as an electric motor.

A grindstone spindle shaft 27, which is movable and rotatable in the Z-axis direction, is supported on the grindstone head 11, and the grindstone 9 is attached to the tip of the grindstone spindle shaft 27. Further, although not shown, the grindstone 9
A projector for projecting the grinding surface is provided above the grinding surface of the workpiece.

With the above construction, the work is placed on the table 21 and positioned in the X-axis, Y-axis and Z-axis directions, and the grindstone 9 is rotated at a predetermined rotational speed to move the grindstone 9 in the X-axis and Y-axis. By moving in the axial and Z-axis directions, the work is ground by the grindstone 9.

A shaping grindstone rotating device 29 is provided at a position of the table 21 facing the grindstone 9. The forming grindstone rotating device 29 includes the grindstone spindle shaft 27.
Rotating device 3 provided with a rotary shaft 31 having an axis orthogonal to
3, a disk-shaped forming grindstone 35 is supported above the rotary shaft 31. The forming grindstone 35
Is rotatable by an electric motor or the like (not shown). The bracket 3 formed on the rotating device 33
7 is fixed to the table 21.

Further, for example, a vibration sensor is provided as a grindstone contact detection sensor 39 at a horizontal position of the bracket 37, and a support rod 41 erected from the bracket 37 measures the diameter of the forming grindstone 35. For example, a displacement sensor is provided as the diameter measuring sensor 43.

With the above configuration, the operation is as shown in FIG.
And referring to FIG. 3, the bracket 3 is attached to the table 21.
By driving the rotating device 33 provided via 7, the forming grindstone 35 is rotated via the rotating shaft 31.
Further, the grindstone 9 is rotated and moved in the X-axis and Y-axis directions to bring the grindstone 9 into contact with the rotating forming grindstone 35.

Next, the grindstone 9 has a radius R'as shown in FIG.
The circular arc interpolation is performed to drive the grindstone 9 and the forming grindstone 35 so that they are always in contact with each other. Then, the R radius of the circular arc interpolation is gradually reduced to correct the mold deformation of the grindstone 9.

The NC device 3 is provided with a measuring cycle program forming means 45 for the grindstone 9.
That is, FIG. 4 shows a configuration block diagram for creating the molding cycle program. In FIG.
Initial conditions, tooling conditions, dressing conditions, and output signals of the sensors 39 and 43 are input to the molding cycle program creating means 45 by an input means such as a keyboard provided on the operation panel to create a molding cycle program. . Then, the output of the measurement and molding cycle program creating means 45 is put into the NC device 3 and NC
The grindstone is formed under the control of the device 3.

Next, the means for determining the arc radius and the arc center of the tip of the grindstone 9 will be described in detail.

With reference to FIGS. 5, 6 and 7, the target arc radius of the tip of the grindstone 9 is r before wear shown in FIG.

As shown in FIG. 5, the current coordinate system is offset in the Y direction by a predetermined value dy. As a result, the center of the arc of the tip of the grindstone 9 changes from P ₀ to P ₁ .

The grindstone 9 and the forming grindstone 35 are brought into contact with each other, and the radius is circularly interpolated by (R ₁ + r + dy) to move the grindstone 9 and gradually cut (the circular arc interpolation radius is reduced).
I will apply.

When cut by dy, as shown in FIG. 6, the circular arc interpolation radius becomes R ₁ + r, the circular arc radius at the tip of the grindstone 9 becomes r ′, and the radius of the forming grindstone 35 becomes R _2. . If the grindstone contact detection sensor 39 detects that the grindstone 9 is in contact with the forming grindstone 35 at all points on the circular arc interpolation, r ′ (= R ₁ + r−R ₂ ) = r
Then, the target arc is restored, and the correction work is completed. At this time, the arc size of the tip of the grindstone 9 is r, and the arc center is dy in the Y direction from the previous arc center.
It is a point that has dropped only (see Fig. 7).

When circular interpolation is performed by cutting only dy,
If the grindstone 9 and the forming grindstone 35 are not in contact with each other at all points, it means that the arc is not restored, and thus the above-described operation is repeated again.

The material of the forming grindstone 35 is such that the grindstone 9 can be shaved and formed. For example, a GC grindstone or molybdenum steel is applicable, but the material is not particularly limited, but the radius of the forming grindstone 35 is controlled. It is necessary that the measurement error is less likely to occur when measured by the outer diameter measuring sensor 43.

With the structure and operation as described above, the grindstone 9 made of superabrasive grains is rotated while moving in the Z-axis direction, and the grindstone spindle shaft 27 is brought into contact with the forming grindstone 35 having a vertical axis. Move in an arc. Forming stone 3 at that time
By detecting the R radius of 5 and the contact between the grindstone 9 and the forming grindstone 35, the arc shape of the tip of the grindstone 9 is finished to a predetermined size while performing tooling and dressing, and at the same time, the arc center is detected.

Therefore, it is possible to eliminate the processing error caused by the visual measurement of the grindstone shape, and it becomes possible to perform high-precision processing. Also, since the radius and position of the arc are revealed,
By incorporating it into the program as a dress cycle, unmanned processing can be performed for a long time.

The present invention is not limited to the above-described embodiments, but can be implemented in other modes by making appropriate changes.

[0040]

As can be understood from the above description of the embodiments, according to the present invention, since the structure is as described in the claims, the super-abrasive process is performed simultaneously with the tooling and the dressing. Detects the arc size and center position of the tip of the grindstone.

Thus, it is possible to eliminate the processing error caused by the visual measurement of the shape of the grindstone, enable high-precision processing, and enable unmanned processing for a long time.

[Brief description of drawings]

FIG. 1 is a perspective view in which a grindstone size measuring device, which is a main part of the present invention, is incorporated in an optical copying grinding machine of an embodiment for carrying out the present invention.

FIG. 2 is an enlarged explanatory view of a II arrow portion in FIG.

3 is an explanatory plan view of FIG.

FIG. 4 is a configuration block diagram of a measurement and molding cycle program creating means.

FIG. 5 is an operation explanatory view.

FIG. 6 is an operation explanatory view.

FIG. 7 is an operation explanatory view.

FIG. 8 is an explanatory view of a projector screen showing a conventional example.

9 is an enlarged explanatory diagram of a portion A in FIG.

FIG. 10 is an explanatory view showing a cut state of the grindstone in FIG. 9.

[Explanation of symbols]

 1 Optical Copy Grinding Machine (Grinding Machine) 3 NC Device (Control Device) 9 Grinding Stone 11 Grinding Stone Head 21 Table 27 Grinding Stone Spindle Shaft 29 Forming Grinding Stone Rotating Device 31 Rotating Axis 35 Forming Grinding Stone 39 Sensor for Grinding Stone Contact Detection 43 Outer Diameter Measurement For measuring 45 means for measuring and forming cycle program

Claims (2)

[Claims] 1. A grinding machine equipped with a grindstone head rotatably supporting a grindstone spindle shaft on which a grindstone for grinding a work is mounted, and the grindstone spindle shaft is rotated while being moved up and down. A radius of the forming whetstone is obtained by bringing the forming whetstone having an axis perpendicular to the axis into contact with the whetstone to move the whetstone in an arc around the forming whetstone.
A grinding wheel size measuring method for a grinding machine, which is characterized by detecting a contact between a grinding wheel and a forming grinding wheel to detect an arc size and a center position of the grinding wheel while performing truing and dressing. 2. A grinder equipped with a grindstone head that rotatably supports a grindstone spindle shaft on which a grindstone for grinding a work is mounted, the grinder being provided on a table on which the work is placed and the grindstone spindle shaft. A forming grindstone rotating device having a forming grindstone attached to a rotating shaft having an orthogonal axis is provided, and this forming grindstone rotating device is provided with a sensor for measuring the outer diameter of the forming grindstone and a sensor for detecting the contact of the grindstone. A grindstone size measuring device in a grinding machine, comprising: a control device provided with means for measuring a grindstone by detection and forming a program.