JP2002172545A - Cutting edge position measuring device and cutting edge position correcting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position the cutting edge position of a tool with high precision in a cutting edge position measuring device and a cutting edge position correcting method. SOLUTION: A measuring device body 25 with a cube sensor 26 is raised on a table 13, and an attachment 30 is moved in a Y- and a Z-direction and the cube sensor 26 is moved in an X-direction to bring the cutting edge of the tool 22 in contact with each measuring surface of the cube sensor 26. Each contact position between the two is used as an XYZ measured attitude position. The measured actual cutting edge position (XYZ measured attitude position) is compared with a design cutting edge position (XYZ initial attitude position) for the calculation of slippage values ΔX, ΔY and ΔZ between the two, on the basis of which the cutting edge position is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting edge position measuring device for measuring the position of a cutting edge of an attachment or a tool mounted on a machine tool such as a machining center, and a cutting edge position correcting method for measuring and correcting the position of the cutting edge. .

[0002]

2. Description of the Related Art For example, in a machining center, a bed supports a table movably along its longitudinal direction, and the bed is provided with a gate-shaped column so as to straddle the table. A horizontal cross rail is fixed, and the saddle is supported by the cross rail so as to be movable in a direction substantially perpendicular to the direction in which the table moves. A ram is supported by the saddle so as to be movable in a vertical direction, and a spindle head is mounted on a lower end of the ram. Therefore, while attaching a predetermined attachment to the spindle head, while holding the workpiece on the table,
By moving the saddle and the ram up, down, left and right while moving the table in this state, predetermined processing can be performed on the workpiece by the attachment.

[0003] In the machining center, and attachment becomes detachable from the spindle head,
Various processes such as milling, drilling, boring, and end milling are possible depending on the attachment to be attached. For example, when performing milling with a universal attachment, by rotating the universal attachment attached to the spindle head about a vertical axis to set the angular position, and rotating about the horizontal axis to set the tilt position, The processing posture is determined. Then, milling is performed on the workpiece on the table in the processing posture of the attachment.

When the angle of the processing surface of the workpiece changes or the processing direction changes during milling with the universal attachment, it is necessary to correct the processing position of the attachment in consideration of the processing efficiency and accuracy of the attachment. There is. Milling That is, come to change the position of the horizontal surface of the workpiece to the milling to inclined surface by the universal attachment, after fixing processing posture of bets by raising the attachment, an inclined surface continuously again lowered Processing.

In such a milling operation, at a position where the processing surface changes from a horizontal surface to an inclined surface, it must be smoothly continued so that a large step is not formed therebetween. However, machine tools such as machining centers have play in assembling each component and backlash of gears.There is a slight shift between the designed edge position calculated from the dimensions of each member and the actual edge position. Therefore, it is difficult to accurately position the cutting edge of the universal attachment. Therefore, conventionally, it is stored in advance cutting edge position corresponding to the plurality of machining posture in universal attachment, so that to position the edge position with high accuracy.

FIG. 7A shows an outline of a universal attachment mounted on a spindle head of a general machining center, and FIG. 7B shows an outline of a storage map of a cutting edge position according to a machining posture in the universal attachment.

As shown in FIG. 7A, a spindle head 102 is mounted below the ram 101 of the machining center so as to be rotatable around a vertical C-axis, and a universal attachment 103 is mounted on the spindle head 102. I have. The universal attachment 103 has an inclined arm 104 rotatable about a horizontal A-axis, and a tool 105 is attached to the tip of the inclined arm 104. Then, FIG.
As shown in the figure, before the work, the edge position of the tool 105 is actually measured and stored for each specific angle that is frequently used, and when the posture of the tool 105 is changed, the stored edge position data is used. I was

[0008]

However, since the memory stores the cutting edge position of the tool 105 for each specific angle that is frequently used, when the tool 105 is used at an angle that is not stored, The cutting edge position data is not stored. Therefore, for example, as shown in FIG.
A tool at the cutting edge position where the axis is 60 ° and the A axis is 30 °
When 105 is used, necessary edge position data is calculated by interpolation based on the edge position data at the front and rear angles. However, the calculated value of the cutting edge position data by interpolation does not take into account the play of assembling the constituent members and the backlash of the gears, so that a slight shift occurs, and the cutting edge position cannot be positioned with high accuracy.

If the specific angle for storing the position of the cutting edge of the tool 105 is reduced, the calculation accuracy of the interpolation increases, but it takes a great deal of time and effort to acquire the cutting edge position data, and a large-capacity memory is required. It becomes necessary and the cost increases.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide a cutting edge position measuring device and a cutting edge position correcting method capable of positioning a cutting edge position of a tool with high accuracy.

[0011]

According to a first aspect of the present invention, there is provided a cutting edge position measuring device, comprising: a measuring device main body disposed near a machine tool; and an upper portion of the measuring device main body. A fixed measuring sensor for measuring the position of the cutting edge of the processing tool, a movable position supported by the measuring device body to cover the periphery of the measuring sensor, and an open position for opening the periphery of the measuring sensor A side cover, a tip cover rotatably supported by the tip of the side cover and covering the tip of the measurement sensor, and a tip cover rotatable between an open position to open the tip of the measurement sensor. And a driving means for synchronously driving the opening and closing operations of the side cover and the front end cover.

In the cutting edge position measuring device according to the second aspect of the present invention, the side cover can be moved up and down by a fluid cylinder, while the tip cover is activated by a connecting link caused by the movement of the side cover. It is characterized in that it can be turned by tilting motion.

According to a third aspect of the present invention, the measurement sensor is a cube sensor having at least five measurement surfaces, and the cutting edge of the processing tool is brought into contact with each of the measurement surfaces to perform tertiary measurement. It is characterized by measuring the original coordinate position.

According to a fourth aspect of the present invention, the measuring sensor is a non-contact optical sensor,
The blade of the processing tool is measured from at least five directions.

According to a fifth aspect of the present invention, there is provided a cutting edge position correcting method, comprising: setting a processing tool mounted on a main spindle to a predetermined processing posture; Measuring the actual position of the cutting edge, comparing the measured position of the cutting edge with the designed cutting position to calculate the amount of deviation between the two, and correcting the position of the cutting edge based on the amount of deviation. Things.

Further, in the cutting edge position correcting method according to the present invention, when correcting the cutting edge position, the detection positions of the measurement sensors serving as the respective references in five directions are measured in advance,
After changing the attitude of the processing tool, the measurement sensor can measure 3
The correction is performed using the detection position measured in the direction.

Further, in the blade position correcting method according to the present invention, the non-contact type optical sensor as the measuring sensor may include:
It is characterized in that the three-dimensional coordinate position is corrected from the plus direction and the minus direction using the sensor detection position.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a longitudinal section of a blade position measuring apparatus according to an embodiment of the present invention, FIG. 2 is a II-II section of FIG. 1, FIG. 3 is a vertical section showing an open state of the blade position measuring apparatus,
FIG. 4 shows an outline of a machining center to which the blade edge position measuring device of the present embodiment is applied, and FIGS. 5 and 6 schematically show a blade edge position correction method.

In the machining center of this embodiment,
As shown in FIG. 4, a pair of guides 12
The table 13 is movably supported along the longitudinal direction of the bed 11 via the, and a workpiece (not shown) can be fixed on the table 13. This bed 1
A column 14 has a gate shape so as to straddle a table 13.
A horizontal cross rail 15 is fixed to the column 14, and a saddle 17 is provided on a front surface of the cross rail 15 via a pair of guides 16 in a horizontal direction substantially orthogonal to the moving direction of the table 13. It is movably supported along. A ram 18 is supported by the saddle 17 so as to be movable in the vertical direction.
A spindle head 19 is mounted on the lower end of the head 8, and a universal attachment 20 is mounted on the spindle head 19.

The universal attachment 20 is detachable from the spindle head 19, is rotatable about the C axis, and the inclined arm 21 is rotatable about the horizontal A axis. Tool 2 in the part
2 are installed.

Therefore, using this machining center,
To perform milling with the universal attachment 20 mounted on the spindle head 19, the workpiece is fixed on the table 13, while the universal attachment 20 is rotated around the C axis to set the cutting direction, and the inclined arm is set. The cutting edge posture is set by rotating the tool 21 about the A axis and setting the inclination angle of the tool 22. In this state, the saddle 17 and the ram 18 are moved up, down, left, and right while the table 13 is being fed and moved, so that the tool 22 can be cut, and the workpiece can be milled.

In the machining center configured as described above, when the posture of the tool 22 is changed during milling or when the attachment is replaced, the cutting edge position of the tool at the attachment attached to the spindle head 19 is measured. position measuring device 23 is a table 1
It is installed adjacent to 3.

In the cutting edge position measuring device 23 of the present embodiment, as shown in FIGS. 1 and 2, a measuring device main body 25 is erected on a gantry 24 fixed to the side of the table 13, and this measurement is performed. A cube sensor 26 as a measurement sensor for measuring the position of the cutting edge of the tool 22 is provided at the upper part of the apparatus main body 25.
Has been fixed. The cube sensor 26 forms a cubic shape having five measurement surface and the lower mounting surface, the tool 2
By bringing the second cutting edge into contact with each measurement surface, its three-dimensional coordinate position can be measured.

A fixed cover 27 in the shape of a square tube surrounding the lower part of the measuring device main body 25 is fixed to the gantry 24. A lifting guide 2 is provided on one side of the measuring device main body 25.
The lifting member 29 is vertically movably supported by 8, and a side cover 30 having a rectangular cylindrical shape slightly larger than the fixed cover 27 is connected to the lifting member 29. An air cylinder 31 is mounted on the other side of the measuring device main body 25, and the tip of the drive rod 32 is connected to the side cover 30 via a bracket 33. Therefore, by expanding and contracting the drive rod 32 by the air cylinder 31, the side cover 30 can be raised and moved to the covering position covering the upper portion of the measuring device main body 25 and the periphery of the cube sensor 26, and lowered. it can be moved to an open position for opening the periphery of the cube sensor 26.

At the upper end of the side cover 30, an upper cover (tip cover) 34 is rotatably supported by a hinge 35, and a rectangular shape is formed between the measuring apparatus main body 25 and the upper cover 34. A connecting link 36 is provided and is rotatable. In addition, a restraining guide 37 that restrains the connecting link 36 when the connecting link 36 stands up is mounted on the upper part of the measuring device main body 25. Therefore, when the side cover 30 is raised, the upper cover 34 can be rotated to a covering position that covers the upper part of the cube sensor 26, and when the side cover 30 is lowered, the upper cover 34 can be rotated.
Can be rotated to an open position where the upper part of the cube sensor 26 is opened.

As described above, by the extension driving of the air cylinder 31, the side cover 30 and the upper cover 34 can be moved to the covering position to cover the cube sensor 26, while the contraction driving of the air cylinder 31 causes the side cover 30 and the upper cover 34 to contract. Cover 3
0 and the upper cover 34 can be moved to the open position in conjunction with each other to open the periphery of the cube sensor 26, and the side cover 3 can be opened by the air cylinder 31 and the connecting link 36.
Drive means for synchronously driving the opening and closing operations of the upper cover 34 and the upper cover 34 is configured.

In this case, as shown in FIG. 3, the side cover 30 and the upper cover 34 are interlocked by the contraction drive of the air cylinder 31 and are moved from the covering position to the open position, whereby the side cover 30 and the upper The cover 34 is positioned below the position of the cube sensor 26 to open the periphery, and the cover 34 is not affected by the position of the universal attachment 20 and the posture of the tool 22 at an arbitrary position of 360 degrees in the horizontal direction of the cube sensor 26. The position of the cutting edge of the tool 22 can be measured.

Hereinafter, a method for measuring the position of the cutting edge and a method for correcting the position of the cutting edge of the tool 22 using the above-described cutting position measuring device 23 will be described. Before performing the work, a reference attachment is attached to the spindle head 19 of the machining center, and a reference tool with a high precision of the cutting edge is used. In order to consider the runout of the spindle, while rotating this reference tool around the C axis,
While moving in the Y and Z directions, the cube sensor 26 is moved in the X direction, the cutting edge of the tool 22 is brought into contact with each measurement surface of the cube sensor 26, and the X, Y, and Z reference coordinate positions of each measurement surface in the machining center are stored. Let it.

Here, as shown in FIG. 5A, a case where the universal attachment 20 is mounted on the spindle head 19 of the machining center, and the two machining surfaces W1 and W2 of the workpiece W are milled by the tool 22. Will be described. First, in order to machine the machining surface W1, the universal attachment 20 is rotated around the C axis to set the cutting direction, and the inclined arm 21 is rotated around the A axis to set the inclination angle of the tool 22. , Set the blade tip attitude. In this case, the position control of the cutting edge position of the tool 22 is performed based on the design numerical values of each component, and X, Y, Z
The initial posture position is stored.

When the X, Y, and Z initial posture positions according to the processing posture of the tool 22 are stored and the cutting edge position is determined, the saddle 17 and the ram 18 are then moved in the vertical and horizontal directions (Y and Z directions). 5B, the table 13 is moved in the front-rear direction (X direction), and as shown in FIG.
The cutting edge of the tool 22 is brought into contact with each measurement surface of the cube sensor 26 at the Y and Z reference coordinate positions.
It is stored as the Y, Z measurement posture position. Then, the measured actual cutting edge position (X, Y, Z measurement posture position) is compared with the designed cutting edge position (X, Y, Z initial posture position), and the deviation amounts ΔX, ΔY, ΔZ of the two are compared. Is calculated, and the cutting edge position is corrected based on the deviation amounts ΔX, ΔY, and ΔZ. That is, by moving the saddle 17 and the ram 18 and moving the table 13 by the shift amounts ΔX, ΔY, ΔZ,
The processing posture of the tool 22 is corrected.

When the cutting edge position of the tool 22 is measured by the cube sensor 26, as shown in FIG.
1 is retracted and the side cover 30 is lowered,
By rotating the upper cover 34 by the rotation of the connection link 36, the side cover 30 and the upper cover 34 are moved to the open position. Then, the periphery of the cube sensor 26 located at the upper part of the measuring device main body 25 is opened, and the cutting edge of the tool 22 can be easily brought into contact.

When the machining posture of the tool 22 is corrected as described above, the saddle 17 and the ram 18 are moved up and down and left and right while moving the table 13 as shown in FIGS. 4 and 5C. Then, a notch is given to the tool 21, and milling is performed on the processing surface W1 of the workpiece W.

When the machining surface W1 is machined to a predetermined area by the tool 22, as shown in FIG.
2 and, in order to machine the machining surface W2, the universal attachment 20 is rotated around the C-axis and the inclined arm 21 is rotated around the A-axis to set the cutting edge posture. X, Y, Z initial posture position with respect to. And, as described above, the saddle 17
By moving the ram 18, the table 13 and the like, FIG.
As shown in (b), the tool 2 is set at the X, Y, Z reference coordinate positions.
The second cutting edge is brought into contact with each measurement surface of the cube sensor 26, and the respective contact positions of the two are stored as X, Y, Z measurement posture positions. Then, the measured actual cutting edge position (X, Y,
Z position) and the designed cutting edge position (X, Y, Z initial position) to compare the deviation amounts ΔX, ΔY, ΔZ between them.
Is calculated, and the cutting edge position is corrected based on the deviation amounts ΔX, ΔY, and ΔZ.

When the machining posture of the tool 22 is corrected as described above, the saddle 17 and the ram 18 are moved up, down, left and right while moving the table 13 as shown in FIGS. 4 and 6C. in, giving a cut to the tool 21, to perform a milling against working surface W1 of the workpiece W.

As described above, in the blade position measuring device of the present embodiment, the measuring device main body 2 erected on the table 13
5, a side cover 30 is movably supported by the measuring apparatus main body 25, and an upper cover 34 is provided on the upper end of the side cover 30.
Is rotatably supported, and the side cover 30 is lowered by driving the air cylinder 31 to contract, and the upper cover 34 is rotated by rotating in conjunction with the connection link 36, and this side cover is rotated. 30 and the upper cover 34 are moved to the open position.

Therefore, the periphery of the cube sensor 26 located above the measuring apparatus main body 25 can be opened without moving the cube sensor 26, and the cutting edge of the tool 22 can be easily brought into contact with the cube sensor 26. it can.

In the method of correcting the position of the cutting edge of the present embodiment, the cutting edge of the tool 22 is moved by moving the attachment 30 in the Y and Z directions and the cube sensor 26 in the X direction. Contact each measurement surface, and let each contact position of both be X, Y, Z measurement posture position,
The measured actual cutting edge position (X, Y, Z measurement posture position) is compared with the designed cutting edge position (X, Y, Z initial posture position) to calculate the deviation amounts ΔX, ΔY, ΔZ between them. The position of the cutting edge is corrected based on the deviation amounts ΔX, ΔY, and ΔZ.

Therefore, whatever the position of the cutting edge of the tool 22 is corrected, it is corrected based on the actual position of the cutting edge (X, Y, Z measurement posture position), such as play of assembling components and backlash of gears. In consideration of the above, the position of the blade edge can be positioned with high accuracy, the labor and time for acquiring the blade edge position data are not required, and the cost is reduced by eliminating the need for a large-capacity memory.

In the above-described embodiment, the cube sensor 26 is provided on the upper portion of the measuring device main body 25, and the side cover 3 is provided.
0 is vertically movable, and the upper cover 34 is provided above the side cover 30. However, a cube sensor is provided on the side of the measuring device main body, and the side cover is horizontally movable. it may be provided with a tip cover part.

In the above-described embodiment, the cutting edge position measuring device 23 is provided on the table 13 of the machining center. However, the mounting position may be any position as long as the tool 22 and the cube sensor 26 can be in contact with each other. Further, although the cube sensor 26 is used as the measurement sensor, the blade of the processing tool may be measured from at least five directions as a non-contact optical sensor.

[0042]

As described in detail in the above embodiment, according to the cutting edge position measuring device of the first aspect of the present invention, the cutting edge position of the processing tool is provided on the upper part of the measuring device main body disposed near the machine tool. While the measurement sensor for measuring the measurement is fixed, the measurement device body is provided with a movable side cover between a covering position covering the periphery of the measurement sensor and an open position for opening the measurement sensor, and a measurement is provided at a tip end of the side cover. Since a rotatable tip cover is provided at a covering position covering the sensor tip and an open position at which the sensor tip is opened, and a driving means for synchronously opening and closing the side cover and the tip cover is provided, the measurement sensor can be moved. In addition, the periphery of the measurement sensor located at the upper part of the measurement device main body can be opened, and the cutting tool edge can be easily brought into contact with the measurement sensor for measurement.

[0043] According to the cutting edge position measuring apparatus of the invention of claim 2, while the movable side cover up and down by a fluid cylinder, by raising 倒動 operation of the connecting link with the front cover to the movement of the side cover Since the cover is rotatable, the two covers can be opened and closed by one drive source, so that the structure can be simplified and the cost can be reduced.

According to the cutting edge position measuring device of the third aspect, the measuring sensor is a cube sensor having at least five measuring surfaces, and the three-dimensional coordinate position is measured by bringing the cutting edge of the processing tool into contact with each measuring surface. Therefore, the position of the cutting edge of the processing tool can be reliably and accurately measured regardless of the position and orientation of the processing tool.

According to the fourth aspect of the present invention, the measuring sensor is a non-contact type optical sensor for measuring the cutting edge of the processing tool from at least five directions. The position of the cutting edge can be measured with high accuracy.

According to a fifth aspect of the present invention, after the processing tool mounted on the main spindle is set to a predetermined processing posture, the processing tool is moved to the reference position, and the cube tool is used to perform the tertiary processing. The actual cutting edge position in the original coordinates is measured, the measured cutting edge position is compared with the designed cutting edge position to calculate a shift amount between the two, and the cutting edge position is corrected based on the shift amount. so it what even cutting edge position and orientation of the processing tool, which is corrected based on the actual edge position, to position the cutting edge position in consideration of assembling backlash or gear backlash components with high precision Can be.

According to the cutting edge position correcting method of the present invention, when correcting the cutting edge position, the detection positions of the measurement sensors, which are the respective references in five directions, are measured in advance, and after the posture of the processing tool is changed. since to carry out correction using the detected position as determined by measurable three directions of the measuring sensor, that whatever the working tool position and orientation measuring the edge position of the working tool to reliably and accurately Can be.

According to the blade position correcting method of the present invention, the non-contact type optical sensor as the measuring sensor uses the sensor detection position from the plus direction and the minus direction in the three-dimensional coordinate position. Since the correction is performed, the position of the cutting edge can be measured with high accuracy in accordance with the position and orientation of the processing tool.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cutting edge position measuring device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a longitudinal sectional view illustrating a state in which a cover is opened in the blade edge position measuring device.

FIG. 4 is a schematic diagram of a machining center to which the blade position measuring device of the present embodiment is applied.

FIG. 5 is a schematic diagram illustrating a method of correcting a blade edge position.

FIG. 6 is a schematic diagram illustrating a method of correcting a blade edge position.

FIG. 7 is a schematic diagram of a universal attachment mounted on a spindle head of a general machining center and a memory map of a cutting edge position.

[Explanation of symbols]

 11 Bed 13 Table 17 Saddle 18 Ram 19 Spindle Head 20 Universal Attachment 22 Tool 23 Blade Position Measurement Device 25 Measurement Device Main Body 26 Cube Sensor (Measurement Sensor) 27 Fixed Cover 30 Side Cover 31 Air Cylinder (Drive Means) 34 Top Cover ( Tip cover) 36 Connecting link (Drive means)

Claims (7)

[Claims] 1. A measuring device main body disposed near a machine tool, a measurement sensor fixed to an upper portion of the measuring device main body for measuring a position of a cutting edge of a processing tool, and movably supported by the measuring device main body. A side cover movable to a covering position for covering the periphery of the measurement sensor and an open position for opening the periphery of the measurement sensor; and the measurement sensor rotatably supported at a tip end of the side cover. A tip cover rotatable between a covering position for covering the tip of the sensor and an open position for opening the tip of the measurement sensor, and driving means for synchronously driving the opening and closing operations of the side cover and the tip cover. Characteristic cutting edge position measuring device. 2. The cutting edge position measuring device according to claim 1, wherein said side cover is movable up and down by a fluid cylinder, and said tip cover is turned upside down by a moving operation of said side cover. A cutting edge position measuring device characterized by being rotatable by an operation. 3. The cutting edge position measuring device according to claim 1, wherein the measuring sensor is a cube sensor having at least five measuring surfaces, and the cutting tool is brought into contact with each of the measuring surfaces so as to be three-dimensional. An edge position measuring device for measuring a coordinate position. 4. The cutting edge position measuring device according to claim 1, wherein the measuring sensor is a non-contact type optical sensor, and measures the cutting edge of the processing tool from at least five directions. apparatus. 5. A processing tool mounted on a spindle is set to a predetermined processing posture, the processing tool is moved to a reference position, and an actual cutting edge position in three-dimensional coordinates is measured by a measurement sensor. A cutting edge position calculated by comparing the calculated cutting edge position with a designed cutting edge position, and correcting the cutting edge position based on the calculated shift amount. 6. The method for correcting the position of the cutting tool according to claim 5, wherein when correcting the position of the cutting edge, a detection position of a measurement sensor serving as a reference in each of five directions is measured in advance, and the posture of the processing tool is changed. A method of correcting the position of the cutting edge, wherein the correction is performed later using detection positions measured in three directions that can be measured by the measurement sensor. 7. The cutting edge position correcting method according to claim 5, wherein the optical sensor of non-contact type as the measuring sensor, using the sensor detection position three-dimensional coordinate position from the respective directions of the positive and negative directions A method for correcting the position of the cutting edge, wherein the correction is performed.