JP6862764B2 - Grinding device and method of manufacturing rolling bearings using it - Google Patents

Description

The present invention relates to a grinding device including a trueing device and a method for manufacturing a rolling bearing using the grinding device.

Conventionally, in the grinding process, the dimensions of the work are measured by a measuring machine such as a touch probe during the grinding process, and the dimensions are reflected in the processing information. However, there is a problem that an error occurs at the time of coordinate conversion between the measuring machine and the grindstone due to the thermal deformation of each component of the grinding device that occurs during machining, which leads to an error in the machining dimensions. As a technique for solving this problem, for example, there is a technique disclosed in Patent Documents 1 and 2.

In the technique of Patent Document 1, the difference between the estimated value of thermal displacement and the actual amount of thermal displacement in each of the plurality of patterns of temperature change is obtained from the linear expansion coefficients of each member of the machine tool changed into a plurality of variables. Identify the coefficient of linear expansion of each member that makes it smaller. Then, the thermal displacement correction amount is calculated based on the identified coefficient of linear expansion, and the position of the moving body of the machine tool is corrected based on the calculated thermal displacement correction amount.

Further, in the technique of Patent Document 2, the scales on the tool side and the work side made of the low expansion alloy are provided on the reference frame made of the low expansion alloy having small thermal deformation, and the scale marks are read by the sensors on the tool side and the work side. .. As a result, the coordinates on the tool side and the coordinates on the work side are obtained while minimizing the influence of thermal deformation. Further, the obtained coordinates are fed back to the feed in the cutting process to minimize the machining error of the workpiece due to the thermal deformation of the machine tool.

Japanese Unexamined Patent Publication No. 2015-30083 Japanese Unexamined Patent Publication No. 2014-237204

However, in the prior art of Patent Document 1, when the grinding machine is large, each part of the grinding machine has a complicated temperature distribution, and the quantification of thermal deformation by the coefficient of linear expansion (identification of the coefficient of linear expansion) becomes complicated. Furthermore, in reality, high technology and advanced equipment are required, such as the need for highly accurate temperature control in the periphery and inside, which poses problems in terms of cost and feasibility.
Further, in the prior art of Patent Document 2, since the measuring means of the work and the tool are different, the coordinate conversion between the work and the tool is performed. Then, in order to eliminate the error of thermal deformation at the time of this coordinate conversion, a low expansion alloy such as an Invar material is used. However, when this method is applied to a large grinding machine, a low expansion alloy, which is generally expensive and difficult to process, is used for a large structural material, which leads to an increase in the price of machine tools and a low expansion alloy. Due to the material characteristics, it may not be possible to use it as a constituent member.

Therefore, the present invention has been made by paying attention to the unsolved problems of such conventional techniques, and it is possible to perform grinding that is simple, low cost, and less likely to be affected by thermal deformation of a machine. It is an object of the present invention to provide an apparatus and a method for manufacturing a rolling bearing using the apparatus.

In order to achieve the above object, the grinding device according to the first aspect of the present invention has a first rotating shaft, a rotating grindstone attached to the tip of the first rotating shaft, and the first rotating shaft. A grinding unit having a first rotational drive source for rotationally driving, a work supporting member for fixing and supporting the work, and the work supporting member are parallel to the first rotating shaft via a second rotating shaft. A work support portion having a support base that rotatably supports the second rotary shaft and a second rotary drive source that rotationally drives the second rotary shaft, and a contact provided between the sensor shaft and the tip end portion of the sensor shaft. A touch probe having the stylus of the formula, a base portion that fixedly supports the grinding portion and the touch probe in parallel with the axis, a measurement reference that serves as a position reference for the touch probe, and a base and the work of the base. A truing portion having a dresser for truing the rotary grindstone provided on a side facing the support portion, a moving drive source, and a guide member are provided, and the base portion is subjected to the driving force of the moving drive source. The moving mechanism unit that moves in the orthogonal biaxial direction along the guide member to the grinding position of the work, the truing position of the rotary grindstone, the measurement position of the shape of the work, and the measurement position of the measurement reference, and the first and the first The second rotary drive source and the mobile drive source are driven and controlled, and the rotary grindstone that rotates at a rotational speed for grinding is brought into contact with the work fixedly supported by the work support member to grind the work. The shape of the work is formed by driving and controlling the grinding unit for processing and the moving drive source to bring the stylus of the touch probe into contact with the work after grinding, which is fixedly supported by the work support. Measurement reference coordinates that perform processing to measure the position coordinates of the measurement reference by contacting the touch probe with the measurement reference by driving and controlling the work shape measurement processing unit that performs the process of measuring The measuring unit, the first rotational drive source, and the moving drive source are driven and controlled, and the rotary grindstone that rotates at the rotational speed for turwing is brought into contact with the dresser of the true wing portion to truing the rotary grindstone. A truing processing unit that performs processing and a truing point coordinate measuring unit that measures the position coordinates of the truing point, which is the contact point of the dresser that comes into contact with the rotating grindstone during truing, are provided.

Further, the position coordinates of the base portion at the end of the truing are represented by the position coordinates of the measurement reference, and the position coordinates of the measurement reference and the position coordinates of the truing point measured by the truing point coordinate measurement unit at the end of the truing. Based on the relative distance of the work and the shape information of the work measured by the work shape measurement processing unit, the position of the base portion corresponding to the representative position coordinates when the rotary grindstone comes into contact with the work during grinding. It includes a base position determining unit that determines the coordinates, and a finishing processing unit that finishes the work based on the position coordinates of the base portion determined by the base position determining unit.

The measurement reference and the dresser are arranged in a positional relationship within a range in which the error of the relative distance due to the thermal influence satisfies the preset target machining accuracy.
Further, in order to achieve the above object, the method for manufacturing a rolling bearing according to one aspect of the present invention targets the raceway ring of the rolling bearing as a work, and uses the grinding device according to the first aspect of the present invention. Manufactures rolling bearings.

According to the present invention, since the relative distance between the truing point and the measurement reference, which are not easily affected by heat, is used to determine the position of the base portion during grinding, stable machining can be performed by suppressing the influence of heat. .. Further, it is possible to suppress the influence of thermal deformation only by changing the positional relationship between the truing point and the measurement reference regardless of the distance via the structure, that is, the size of the grinding device. As a result, it is not necessary to consider the coefficient of linear expansion of the structural material, so that there are no restrictions on the material as compared with the conventional case. Further, since it is not necessary to perform complicated thermal deformation control, it is not necessary to upgrade the equipment, and the cost for that is not required. That is, it is possible to position the base portion while suppressing the influence of thermal deformation, which is simpler and lower cost than the conventional one.

It is a figure which shows an example of the whole structure of the 1st grinding apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows the structural example of the moving mechanism part which moves with respect to the 2nd base part. (A) and (b) are schematic views showing a configuration example of a touch probe. It is a block diagram which shows an example of the hardware composition of the 1st control device which concerns on 1st Embodiment. It is a block diagram which shows an example of the functional structure of the 1st control device which concerns on 1st Embodiment. It is a flowchart which shows an example of the processing procedure of the groove processing processing of the outer ring work which concerns on 1st Embodiment. It is a flowchart which shows an example of the processing procedure of the work information measurement processing which concerns on 1st Embodiment. It is a flowchart which shows an example of the processing procedure of the base position determination processing which concerns on 1st Embodiment. (A) to (e) are schematic diagrams for explaining a series of operations until the base position of the 1st grinding apparatus of 1st Embodiment is determined. It is a schematic diagram which shows an example of the positional relationship between the grindstone for groove grinding at the end of tsuruing and the first tsuruing device. It is a figure which shows the positional relationship between the work for an outer ring, the base part, and the 1st truing device when a grindstone for groove grinding is brought into contact with a 1st groove bottom part. It is a figure for demonstrating the distance through the structure of each component including the groove grinding part of the 1st grinding device, a touch probe, a processing point, a 1st turreting device, and a measurement reference. It is a figure which shows an example of the whole structure of the 2nd grinding apparatus which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the positional relationship between the grindstone for groove grinding at the end of turreting, and the second grooving apparatus. It is a block diagram which shows an example of the functional structure of the 2nd control device which concerns on 2nd Embodiment. It is a flowchart which shows an example of the processing procedure of the groove processing processing of the inner ring work which concerns on 2nd Embodiment. It is a flowchart which shows an example of the processing procedure of the reference grindstone diameter measurement processing. It is a flowchart which shows an example of the processing procedure of the thermal deformation correction processing. (A) to (d) are schematic diagrams for explaining a series of operations for measuring a reference grindstone diameter of the second embodiment. (A) is a diagram showing an example of the positional relationship between the proximity detection boundary, the grindstone for groove grinding, and the truing point when measuring the reference grindstone diameter, and (b) is a diagram showing the grindstone diameter at the end of truing. It is a figure which shows an example of the positional relationship between a proximity detection boundary, a grindstone for groove grinding, and a truing point. (A) to (d) are schematic diagrams for explaining a series of operations for measuring a grindstone diameter in consideration of thermal deformation of the second embodiment. It is a figure which shows the positional relationship between the inner ring work, the base part, and the 2nd truing device when the grindstone for groove grinding is brought into contact with the 3rd groove bottom part. (A) is a schematic diagram showing a modified example of the first embodiment, and (b) is a schematic diagram showing a modified example of the second embodiment.

Next, the first and second embodiments of the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. However, it should be noted that the drawings are schematic and the vertical and horizontal dimensions and scale of the members or parts may differ from the actual ones. Therefore, the specific dimensions and scale should be judged in consideration of the following explanation. In addition, it goes without saying that there may be parts in which the relations and ratios of the dimensions of the drawings are different from each other.

Further, the first and second embodiments shown below exemplify devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is based on the material of the component parts. The shape, structure, arrangement, etc. are not specified as follows. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.
(First Embodiment)
(Constitution)
In the first grinding device 1A according to the first embodiment, for example, a groove serving as a rolling path for balls is formed on the peripheral surface of a work such as a raceway ring (outer ring and inner ring) of a ball bearing by grinding with a rotary grindstone. It is a device to do.

As shown in FIG. 1, the first grinding device 1A includes a grinding measuring section 2, a work support section 3, a first growing device 4A, and a first control device 5A.
The grinding measurement unit 2 includes a base unit 20, a groove grinding unit 21, and a touch probe 22. The base portion 20 includes a first base portion 23 and a second base portion 26.
The grinding measurement unit 2 further includes a first left linear motion guide device 24L, a first right linear motion guide device 24R, and a first ball screw device 25 as a moving mechanism unit. In addition, it includes a second left linear motion guide device 27L, a second right linear motion guide device 27R, and a second ball screw device 28.

The groove grinding unit 21 includes a grindstone 21a for groove grinding, a grindstone spindle 21b as a first rotating shaft, a grindstone spindle housing 21c accommodating the grindstone spindle 21b, and a first rotational drive source of the grindstone spindle 21b. It is provided with a grindstone spindle motor 21d.
The grindstone 21a for groove grinding is composed of a disk-shaped rotary grindstone, and is concentrically attached to the tip of the grindstone spindle 21b. As the grindstone 21a for groove grinding, one having an outer diameter dimension and a thickness dimension according to the type of the work to be groove grinded is attached. Further, in the grindstone 21a for groove grinding, a convex grindstone surface matching the groove shape formed on the work is formed on the outer peripheral surface by truing (reshaping) by the first truing device 4A.

With this configuration, the groove grinding unit 21 rotates the grindstone spindle 21b by the grindstone spindle motor 21d to rotate the grindstone 21a attached to the tip of the grindstone spindle 21b at the rotational speed for grinding. Then, by bringing the rotating grindstone for groove grinding 21a into contact with the peripheral surface of the work W, the contact surface is ground to form a groove.
On the other hand, the touch probe 22 is used when measuring the position information of the surface of the groove ground by the groove grinding unit 21. The details of the touch probe 22 will be described later.

Here, in the first embodiment, the entire coordinate system of the first grinding device 1A has an X-axis in the left-right direction and a Z-axis in the up-down direction (height direction) when viewed from the front, like the coordinate axes shown in FIG. , Is defined as a Cartesian coordinate system with the depth direction as the Y axis. The symbols "+" and "-" in the coordinate axes in FIG. 1 indicate the plus direction and the minus direction of each axis.
The groove grinding portion 21 and the touch probe 22 are fixedly supported by the first base portion 23 in a state of protruding along the Z axis from the end of the rectangular first base portion 23 in the negative direction of the Z axis. There is. In addition, the groove grinding portion 21 and the touch probe 22 are fixedly supported by the first base portion 23 in parallel with the axis with a predetermined gap in the X-axis direction.

The first left linear motion guide device 24L is a linear first left guide rail 24Lr fixedly supported on the second base portion 26 via a bolt, and along the first left guide rail 24Lr. It is provided with a first left slider 24Ls attached to the first left guide rail 24Lr so as to move linearly via a bearing mechanism.
The first right linear motion guide device 24R sandwiches the first ball screw device 25 in between, and the second base portion 26 is parallel to the first left guide rail 24Lr of the first left linear motion guide device 24L. It is provided with a linear first right guide rail 24Rr fixedly supported by a bolt on the top. Further, it is provided with a first right slider 24Rs attached to the first right guide rail 24Rr via a bearing mechanism so as to move linearly along the first right guide rail 24Rr.

The first ball screw device 25 includes a first ball screw shaft 25B, a first ball screw nut 25N, a first stopper 25STP, a Z-axis drive motor 25M, and a Z-axis encoder 25E. There is.
The first ball screw shaft 25B has a spiral screw groove on the outer peripheral surface, and the first ball screw nut 25N has a screw groove facing the screw groove of the screw shaft on the inner peripheral surface, and both screws. A plurality of balls are tumblably loaded in a spiral ball rolling path formed by a groove.

The first ball screw shaft 25B is arranged in parallel with the first left guide rail 24Lr and the first right guide rail 24Rr. Further, one end side is connected to the drive shaft of the Z-axis drive motor 25M via, for example, a coupling, and the other end side is supported by the first stopper 25STP via, for example, a bearing.
The first stopper 25STP is fixedly supported on the second base portion 26 via a bolt to prevent the first ball screw nut 25N from coming off on the other end side of the first ball screw shaft 25B.

The Z-axis drive motor 25M, which is a mobile drive source, is a servomotor that applies a rotational force to the first ball screw shaft 25B, and is a motor control from a first control device 5A via an electric cable (not shown). It is driven and controlled by a signal. Further, the Z-axis drive motor 25M is fixedly supported on the second base portion 26 via a bolt to prevent the first ball screw nut 25N from falling off on one end side of the first ball screw shaft 25B. ..

The Z-axis encoder 25E is an incremental rotary encoder that detects the motor rotation angle position θmz of the Z-axis drive motor 25M. The Z-axis encoder 25E transmits the detected motor rotation angle position θmz to the first control device 5A via an electric cable (not shown).
With this configuration, the first ball screw shaft 25B is rotationally driven by the rotational driving force of the Z-axis drive motor 25M, so that the first ball screw nut 25N becomes the first ball screw via the rolling of the ball. It moves along the shaft 25B. Along with this, the first left slider 24Ls moves linearly along the first left guide rail 24Lr, and the first right slider 24Rs moves linearly along the first right guide rail 24Rr.

Here, the first base portion 23 is fixed to the end faces of the first left slider 24Ls, the first right slider 24Rs, and the first ball screw nut 25N on the front side in the Y-axis direction via bolts, respectively. There is. Therefore, when the first base portion 23 moves in the Z-axis direction, the groove grinding portion 21 and the touch probe 22 fixedly supported by the first base portion 23 move in the Z-axis direction.
On the other hand, as shown in FIGS. 1 and 2, the second left linear motion guide device 27L includes a linear second left guide rail 27Lr fixedly supported on a column (not shown) via a bolt. It is provided with a second left slider 27Ls attached to the second left guide rail 27Lr via a bearing mechanism so as to move linearly along the second left guide rail 27Lr.

The second right linear motion guide device 27R is fixedly supported on the column in parallel with the second left guide rail 27Lr of the second left linear motion guide device 27L with the second ball screw device 28 sandwiched between them. It is equipped with a straight second right guide rail 27Rr. Further, it is provided with a second right slider 27Rs attached to the second right guide rail 27Rr via a bearing mechanism so as to move linearly along the second right guide rail 27Rr.

The second ball screw device 28 includes a second ball screw shaft 28B, a second ball screw nut 28N, a second stopper 28STP, an X-axis drive motor 28M, and an X-axis encoder 28E. There is.
The second ball screw shaft 28B has a spiral screw groove on the outer peripheral surface, and the second ball screw nut 28N has a screw groove facing the screw groove of the screw shaft on the inner peripheral surface, and both screws. A plurality of balls are tumblably loaded in a spiral ball rolling path formed by a groove.

The second ball screw shaft 28B is arranged in parallel with the second left guide rail 28Lr and the second right guide rail 28Rr. Further, one end side is connected to the drive shaft of the X-axis drive motor 28M via, for example, a coupling, and the other end side is supported by the second stopper 28STP, for example, via a bearing.
The second stopper 28STP is fixedly supported on the column via a bolt to prevent the second ball screw nut 28N from coming off on the other end side of the second ball screw shaft 28B.

The X-axis drive motor 28M, which is a mobile drive source, is a servomotor that applies a rotational force to the second ball screw shaft 28B, and is a motor control from a first control device 5A via an electric cable (not shown). It is driven and controlled by a signal. Further, the X-axis drive motor 28M is fixedly supported on the column via bolts to prevent the second ball screw nut 28N from coming off on one end side of the second ball screw shaft 28B.

The X-axis encoder 28E is an incremental rotary encoder that detects the motor rotation angle position θmx of the X-axis drive motor 28M. The X-axis encoder 28E transmits the detected motor rotation angle position θmx to the first control device 5A via an electric cable (not shown).
With this configuration, the second ball screw shaft 28B is rotationally driven by the rotational driving force of the X-axis drive motor 28M, so that the second ball screw nut 28N becomes the second ball screw via the rolling of the ball. It moves along the axis 28B. Along with this, the second left slider 27Ls moves linearly along the second left guide rail 27Lr, and the second right slider 27Rs moves linearly along the second right guide rail 27Rr.

Here, the second base portion 26 is fixed to the end faces of the second left slider 27Ls, the second right slider 27Rs, and the second ball screw nut 28N on the front side in the Y-axis direction via bolts, respectively. There is. Therefore, when the second base portion 26 moves in the X-axis direction, the first base portion 23 fixedly supported by the second base portion 26 moves in the X-axis direction. That is, since the entire base portion 20 moves in the X-axis direction, the groove grinding portion 21 and the touch probe 22 fixedly supported by the first base portion 23 also move in the X-axis direction.

With the above configuration, the groove grinding portion 21 and the touch probe 22 can be moved in the X-axis direction and the Z-axis direction in FIG. Although the moving mechanism in the Y-axis direction is not shown, the base portion 20 of the first grinding device 1A may be configured to be movable in the Y-axis direction as well.
As shown in FIG. 1, the work support portion 3 can rotate the support base 30, the table 31 provided on the support base 30, the work support member 32 provided on the table 31, and the table 31. It is provided with a work rotation spindle 33, which is a second rotation axis to support. Further, it includes a work rotation spindle housing 34 that houses the work rotation spindle 33 inside, and a work rotation motor 35 that is a second rotation drive source for rotationally driving the work rotation spindle 33.

The work support member 32 is composed of a magnet chuck that fixedly supports the work W by magnetic force. Further, the work supporting member 32 is prepared in various shapes according to the type of the work W, and the corresponding shape can be replaced according to the type of the work to be ground. ing. Here, in the first embodiment, the types of the work W are roughly classified into a work W for the outer ring of the bearing and a work Wi for the inner ring.

The work W illustrated in FIG. 1 is a work W for an outer ring of a ball bearing, and in order to form a groove on the inner peripheral surface of the outer ring, the work W for the outer ring is magnetically applied to the upper end of the cylindrical work supporting member 32. It is fixedly supported by adsorbing with. In the following description, when it is not necessary to distinguish between the outer ring work Wo and the inner ring work Wi, it may be simply described as "work W".
The work rotation motor 35 includes an absolute rotary encoder 36E (hereinafter, may be referred to as “work rotation axis encoder 36E”) that detects the motor rotation angle position. Then, the motor rotation angle position θm detected by the work rotation axis encoder 36E is configured to be transmitted to the first control device 5A via an electric cable (not shown).

With this configuration, the work support portion 3 rotates the table 31 by rotationally driving the work rotation spindle 33 by the work rotation motor 35, and is fixedly supported on the table 31 via the work support member 32. Rotate the work W.
The first truing device 4A includes a dresser base 40, a diamond dresser 41 fixedly supported by the dresser base 40, and a measurement reference 42 fixedly supported on the upper part of the dresser base 40.

The diamond dresser 41 has a tip portion Pt formed by polishing diamond into a conical shape, and when forming a convex grindstone surface matching the groove shape formed on the work W on the outer peripheral surface of the grindstone 21a for groove grinding. Used. Hereinafter, the tip Pt of the diamond dresser 41 may be referred to as a “truing point Pt”.
Here, the first truing device 4A adjusts the rotation speed of the groove grinding wheel 21a, the feed rate in the X-axis direction with respect to the diamond dresser 41, and the feed rate in the Z-axis direction to adjust the groove grinding wheel 21a. , Truing (reshape) or dressing (sharpening).

Specifically, the rotation speed of the grindstone spindle 21a is controlled by controlling the rotation speed of the grindstone spindle motor 21d by the first control device 5A. In addition, by controlling the rotation speed of the X-axis drive motor 28M, that is, the moving speed of the groove grinding wheel 21a in the X-axis direction, the cutting speed of the groove grinding wheel 21a with respect to the diamond dresser 41 is controlled. Further, by controlling the rotation speed of the Z-axis drive motor 25M, that is, the moving speed of the groove grinding wheel 21a in the Z-axis direction, the feed rate of the groove grinding wheel 21a with respect to the diamond dresser 41 is controlled.

Further, the first truing device 4A of the first embodiment is a measuring instrument 45 (for example, an electric micrometer) that measures the reference coordinates (Xt, Zt) of the truing point Pt of the diamond dresser 41 and the amount of wear ΔXt with respect to the reference coordinates. ) Is provided. The measuring instrument 45 is mounted so as to be precisely positioned with respect to the measuring reference 42. Therefore, the measured value from the measuring device 45 can be converted into the X-axis coordinate value and the Z-axis coordinate value in the coordinate system of the entire device.

The measurement reference 42 is a position reference of the touch probe 22, and is composed of, for example, a metal columnar member. The measurement reference 42 is used to correct the positional error of the touch probe 22 by periodically measuring the measurement point Pm with the touch probe 22. In the first embodiment, the measurement reference 42 is provided on the upper part of the dresser base 40. The measurement reference 42 has a position that can be measured by the touch probe 22, and the error of the relative distance between the position coordinates of the measurement reference 42 due to the thermal influence and the position coordinates of the truing point Pt satisfies the preset target machining accuracy. It is provided at a position within the range. Specifically, the measurement reference 42 and the diamond dresser 41 are, for example, when the frame of the dresser base 40 is made of iron and the target processing accuracy is set to 5 [μm] or less, the distance between the two structures is 41. It is provided in a positional relationship of [cm] or less. Here, the coefficient of linear expansion of iron is 12.1 × ^10-6 , and when the temperature changes by 1 [° C.], the length changes by 12.1 [μm] per 1 [m]. Further, the first truing device 4A is provided at a position on the support base 30 where the thermal influence is small (for example, a position as far as possible from the heat generating source). If the target machining accuracy cannot be satisfied due to the temperature environment, the temperature change may be controlled within 1 [° C.] by, for example, passing a coolant for grinding through the dresser base 40.

The first control device 5A drives and controls the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M, and dresses using the first turwing device 4A. , The groove grinding process by the groove grinding unit 21, the work information measurement process by the touch probe 22, the base position determination process based on the measurement information, and the like are executed. The detailed configuration of the first control device 5A will be described later.

(Structure of touch probe 22)
Next, the configuration of the touch probe 22 of the present embodiment will be described with reference to FIG.
As shown in FIG. 3A, the touch probe 22 includes a probe housing 22a and a probe head 22b.
The probe head 22b includes a probe shaft 22s and a stylus 22t. The stylus 22t includes a first arm portion 22c and a second arm portion 22e that project back to back from the outer peripheral surface of the tip end portion of the probe shaft 22s via the tip end portion. Further, it includes a third arm portion 22g and a fourth arm portion 22i that project back-to-back outward from the outer peripheral surface of the tip end portion of the probe shaft 22s in a direction orthogonal to the first arm portion 22c and the second arm portion 22e. Furthermore, the stylus 22t includes the first tip sphere 22d and the second tip sphere 22f formed at the tips of the first arm portion 22c and the second arm portion 22e, and the third arm portion 22g and the fourth arm portion 22i. It includes a third tip sphere 22h and a fourth tip sphere 22j formed at the tip.

Further, although not shown, the touch probe 22 includes a pressure sensor provided inside the probe housing 22a and a transmission member that transmits a force corresponding to the inclination of the probe head 22b to the pressure sensor.
With this configuration, the first tip ball 22d comes into contact with the surface of the groove and is pushed, so that the probe head 22b is tilted in the direction opposite to the pushing direction. As a result, the transmission member is pushed and the pressing pressure Pr1 is detected by the pressure sensor. Similarly, when the second tip sphere 22f comes into contact with the surface of the groove and is pushed, the pushing pressure Pr2 is detected, and when the third tip sphere 22h comes into contact with the surface of the groove and is pushed, the pushing pressure Pr3 is released. Detected. Further, when the fourth tip ball 22j comes into contact with the surface of the groove and is pushed, the pushing pressure Pr4 is detected.

Hereinafter, the first tip sphere 22d, the second tip sphere 22f, the third tip sphere 22h, and the fourth tip sphere 22j may be abbreviated as simply "tip spheres 22d, 22f, 22h, and 22j".
The detected values Pr1, Pr2, Pr3 and Pr4 of the detected pressing force are transmitted to the first control device 5A via an electric cable (not shown).
(Hardware configuration of the first control device 5A)
Next, the hardware configuration of the first control device 5A will be described with reference to FIG.

The first control device 5A includes a computer system. As shown in FIG. 4, this computer system includes a CPU (Central Processing Unit) 60, a RAM (Random Access Memory) 62, and a ROM (Read Only Memory) 64. In addition, various internal and external buses 68 and an input / output interface (I / F) 66 are provided.
The CPU 60, RAM 62, and ROM 64 are connected via various internal and external buses 68, and the touch probe 22 (pressure sensor) and the first truing device 4A (wear amount measuring device) are connected to the bus 68 via the I / F 66. ), The X-axis encoder 28E and the Z-axis encoder 25E are connected. Further, a storage device (Secondary Storage) 70 such as an HDD (Hard Disk Drive), an output device 72 such as an LCD monitor, an operation panel, a keyboard, an input device 74 such as a mouse, and the like are connected.

Then, when the power is turned on, the system program such as BIOS stored in the ROM 64 or the like is stored in the storage device via various dedicated computer programs stored in the ROM 64 in advance or a storage medium such as a CD-ROM or a DVD-ROM. Various dedicated computer programs installed in the 70 are loaded into the RAM 62, and the CPU 60 makes full use of various resources according to the instructions described in the program loaded in the RAM 62 to perform predetermined control and arithmetic processing, thereby performing each function described later. Can be realized on the software.

(Functional configuration of the first control device 5A)
Next, the functional configuration of the first control device 5A will be described with reference to FIG.
As shown in FIG. 5, the first functional configuration unit 50A of the first control device 5A includes a groove grinding processing unit 51, a work information measuring unit 52, a measurement reference coordinate measuring unit 53, and a trueing processing unit 54. , A base position determining unit 55 is provided.

The groove grinding unit 51 corresponds to the type of groove to be formed (for example, the model number of the product or the work) stored in the storage device 70 in advance in response to the grinding start command input via the input device 74. Data necessary for groove grinding, such as target groove shape data and processing condition data, is read from the storage device 70. Then, based on the read data, first, the grooving process of the groove grinding wheel 21a is executed, and then the groove grinding process is executed.

Here, as the target groove shape data, one data is prepared for each model number of the work to be machined. Specifically, it is data including information related to the target groove cross-sectional shape.
Further, the machining condition data is data of machining conditions predetermined by the shape, material, etc. of the work W, the type of the grindstone 21a for groove grinding, and the like. For example, it is data set for each model number of a product or a work.

Further, when the work to be machined is the work Wo for the outer ring, the groove grinding unit 51 repeatedly executes the grinding process and determines that the execution timing of the second and subsequent truing has come, and issues a work information measurement command. Output to the information measurement unit 52.
The work information measuring unit 52 uses the touch probe 22 to measure the distance between the groove portion of the outer ring work Wo after the groove grinding process and the groove bottom portion facing the groove portion. In addition, the coordinates of the center position Rci of the outer ring work Wo are measured.

Here, in the first embodiment, as shown in FIG. 1, the first groove bottom portion Db1 which is the groove bottom portion of the groove portion on the processing point Pg side of the groove formed on the outer ring work Wo after the groove grinding process. The first groove bottom diameter Di, which is the distance between and the second groove bottom portion Db2, which is the groove bottom portion of the groove portion facing the same, is measured. In addition, the first center coordinates (Xci, Zci), which are the coordinates of the center position Rci of the outer ring work Wo, are measured. Here, the machining point Pg is a contact point between the grindstone 21a for groove grinding and the work W during groove grinding.

Specifically, the work information measuring unit 52 first uses the touch probe 22 in response to the work information measuring command input from the groove grinding processing unit 51 to form the groove shape of the outer ring work Wo after the groove grinding process. To measure. This process is executed by driving and controlling the work rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M.
Specifically, the work information measuring unit 52 measures two groove shapes, a groove portion corresponding to the machining point Pg and a groove portion at a position facing the groove portion.

That is, the work information measuring unit 52 first drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M with respect to the position of the groove portion corresponding to the machining point Pg. Then, the probe head 22b is moved in each axial direction necessary for alignment with the measurement position and stopped at a preset Z-axis coordinate position in front of the groove portion to be measured. At this time, the tip sphere used for the measurement of each groove portion is determined in advance. Here, for example, the second tip sphere 22f is used for the measurement on the processing point Pg side, and the first tip sphere 22d is determined to be the tip sphere used for the measurement on the opposite side. Therefore, first, the second tip sphere 22f is moved so as to come to the front of the groove portion corresponding to the processing point Pg. Subsequently, the X-axis drive motor 28M is driven and controlled, the probe head 22b is moved in the X-axis direction, the second tip sphere 22f is brought into contact with the groove surface, and the motor rotation angle positions θmx and θmx at the time of contact are measured. .. Further, the X-axis coordinate value and the Z-axis coordinate value of the contact position are calculated from the motor rotation angle positions θmx and θmx, and the X-axis coordinate value and the Z-axis coordinate value are combined and stored in the RAM 62. This position measurement is repeated while changing the Z-axis coordinate position along the groove portion, and the groove shape on the machining point Pg side is measured.

Subsequently, the work information measuring unit 52 drives and controls the X-axis drive motor 28M so that the first tip sphere 22d facing the back surface of the second tip sphere 22f is positioned so as to face the groove portion corresponding to the machining point Pg. Move to the front of a certain groove part. Subsequently, the Z-axis drive motor 25M is driven and controlled to move the probe head 22b in the Z-axis direction and stop the tip sphere at a preset Z-axis coordinate position. Then, the X-axis drive motor 28M is driven and controlled, the probe head 22b is moved in the X-axis direction, the first tip ball 22d is brought into contact with the groove surface, and the motor rotation angle positions θmx and θmx at the time of contact are measured. .. Further, the X-axis coordinate value and the Z-axis coordinate value of the contact position are calculated from the motor rotation angle positions θmx and θmx, and the X-axis coordinate value and the Z-axis coordinate value are combined and stored in the RAM 62. This position measurement is repeated while changing the Z-axis coordinate position along the groove portion, and the groove shape on the opposite side is measured.

Based on the measurement result of the groove shape, the work information measuring unit 52 is the deepest portion of the groove with respect to the two facing groove portions of the outer ring work Wo, that is, the first and second portions on the machining point side and the facing side. The first and second groove bottom coordinates (X1, Z1) and (X2, Z2), which are the coordinates of the groove bottoms Db1 and Db2, are specified. In addition, Z1 = Z2. Then, based on the specified first and second groove bottom coordinates (X1, Z1) and (X2, Z2), the distance between the groove bottoms (first groove bottom diameter) Di and the center position Rci of the outer ring work Wo. The first center coordinates (Xci, Zci), which are the coordinates, are calculated. Then, the calculated first groove bottom diameter Di and the first center coordinates (Xci, Zci) are stored in the RAM 62.

When the work information measuring unit 52 finishes measuring the first groove bottom diameter Di and the first center coordinates (Xci, Zci), the work information measuring unit 52 outputs a measurement reference coordinate measurement command to the measuring reference coordinate measuring unit 53.
Returning to FIG. 5, the measurement reference coordinate measurement unit 53 uses the touch probe 22 to perform the position coordinates (Xr, Zr) of the measurement point Pm of the measurement reference 42 of the first truing device 4A (hereinafter, “measurement reference position”. Coordinates (Xr, Zr) "may be described).

Specifically, the measurement reference coordinate measurement unit 53 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M in response to the measurement reference coordinate measurement command input from the work information measurement unit 52. As a result, the probe head 22b is moved in the X-axis direction and the Z-axis direction, and the tip sphere (for example, the second tip sphere 22f) determined in advance for measurement is brought into contact with the measurement point Pm of the measurement reference 42. Then, the motor rotation angle positions θmx and θmx at the time of contact are measured. Further, the X-axis coordinate value Xr and the Z-axis coordinate value Zr of the contact position are calculated from the motor rotation angle positions θmx and θmx, and the X-axis coordinate and the Z-axis coordinate are combined to form a measurement reference position coordinate (Xr, Zr). ) Is stored in the RAM 62.

The measurement reference coordinate measurement unit 53 outputs a truing execution command to the truing processing unit 54 when the measurement of the measurement reference position coordinates (Xr, Zr) is completed.
The grooving processing unit 54 executes the grooving of the grindstone 21a for groove grinding by using the first grooving device 4A.
Specifically, the truing processing unit 54 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M to drive and control the grindstone 21a for grooving, and the truing point Pt of the diamond dresser 41 of the first truing device 4A. Move to a position near. After that, the grindstone spindle motor 21d is driven and controlled, and the grindstone 21a for groove grinding is rotated at the rotation speed for trueing. Then, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled to move the groove grinding grindstone 21a toward the truing point Pt at the truing cutting speed in the X-axis direction, and for truing. Moves in the Z-axis direction at the feed rate of. As a result, the grindstone 21a for groove grinding is slewed. When the truing is completed, the truing processing unit 54 causes the measuring instrument 45 of the first truing device 4A to measure the amount of wear ΔXt with respect to the reference position (Xt, Zt) of the truing point Pt of the diamond dresser 41. Then, the measured amount of wear ΔXt is stored in the RAM 62. In addition, the measurement reference position coordinates (Xr, Zr) stored in the RAM 62 are set as the representative coordinates of the base portion 20 at the end of turwing (hereinafter, may be referred to as "base coordinates (Xb, Zb)"). To do. Here, in the first embodiment, the base coordinates (Xb, Zb) are managed as variables. Therefore, by substituting the measurement reference position coordinates (Xr, Zr) into the base coordinates (Xb, Zb) which are variables, the base coordinates (Xb, Zb) at the end of turwing are determined.

When the measurement of the truing and the amount of wear ΔXt is completed, the truing processing unit 54 outputs a base position determination command to the base position determination unit 55.
The base position determining portion 55 determines the position of the base portion 20 when the grindstone 21a for groove grinding and the first groove bottom portion Db1 on the processing point Pg side of the outer ring work Wo come into contact with each other.
Specifically, the base position determination unit 55 is based on the reference position coordinates (Xt, Zt) of the truing point Pt and the wear amount ΔXt stored in the RAM 62, and the coordinates (Xt + ΔXt, Zt) of the truing point Pt at the end of the truing. ) Is calculated. Next, from these coordinates (Xt + ΔXt, Zt) and the measurement reference position coordinates (Xr, Zr) stored in the RAM 62, the coordinates of the truing point Pt at the end of truing are obtained according to the following equations (1) and (2). The relative distance (Xrt, Zrt) from the measurement reference position coordinates (Xr, Zr) is calculated. Hereinafter, this relative distance (Xrt, Zrt) may be described as "first relative distance (Xrt, Zrt)".

Xrt = Xr- (Xt + ΔXt) ... (1)
Zrt = Zr-Zt ... (2)
Subsequently, from the calculated first relative distance (Xrt, Zrt), the first groove bottom diameter Di stored in the RAM 62, and the first center coordinates (Xci, Zci), the following equations (3) and (4) ), The base coordinates (Xb, Zb), which are the coordinates of the base portion 20 when the groove grinding wheel 21a and the first groove bottom portion Db1 of the outer ring work Wo come into contact with each other, are calculated.

Xb = Xci + Xrt + Di / 2 ... (3)
Zb = Zci + Zrt ・ ・ ・ (4)
Then, the calculated base coordinates (Xb, Zb) are stored in the RAM 62. That is, the calculated value is substituted into the base coordinates (Xb, Zb) which are variables.
In this way, the first relative distance (Xrt, Zrt) between the trueing point Pt and the measurement point Pm, which are not easily affected by heat, and the first groove bottom diameter Di and the first center coordinates, which are not affected by heat. By determining the base coordinates from (Xci, Zci), the error due to thermal deformation is corrected.

Then, when the base coordinates are determined, the base position determination unit 55 outputs a position determination end notification to the groove grinding process unit 51.
When the groove grinding unit 51 receives the position determination end notification from the base position determination unit 55, the groove grinding unit 51 subsequently finishes the outer ring work Wo using the base coordinates (Xb, Zb) stored in the RAM 62. ..

(Groove processing of work Wo for outer ring)
Next, the processing procedure of the groove processing of the outer ring work Wo of the first embodiment will be described with reference to FIG.
When the program is executed by the CPU 60 of the first control device 5A and the groove processing of the outer ring work Wo is started, the process first proceeds to step S100 as shown in FIG.

In step S100, the groove grinding processing unit 51 reads the target groove shape data and the processing condition data corresponding to the model number of the outer ring work Wo to be ground from the storage device 70 into the RAM 62, and proceeds to step S102.
In step S102, the groove grinding processing unit 51 performs groove shape management processing based on the processing condition data read into the RAM 62. After that, the process proceeds to step S104.

Here, in the groove shape management process, the groove grinding wheel 21a is trued into a shape capable of forming the groove shape to be formed by using the first grooving device 4A, and the grooving grindstone 21a is formed. It includes a process of grinding a groove on the peripheral surface of the master work Wom for the outer ring. Further, the groove shape management process includes a process of measuring the position reference master for the outer ring work Wo to be processed first and storing the measured value as the initial value of the position reference master in the RAM 62.

In step S104, the groove grinding process section 51 executes the groove grinding process. After that, the process proceeds to step S106.
Here, in the groove grinding process of the first embodiment, the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled, and first, for the outer ring. A groove is roughly ground on the inner peripheral surface of the work Wo using a grindstone 21a for groove grinding. Subsequently, the work rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled, and the groove shape of the outer ring work Wo is measured by the touch probe 22. Subsequently, a dimensional error is calculated based on this measurement result, and based on the calculated dimensional error, the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled. Therefore, it is a process of finishing the groove.

At this time, before executing the base position determination process in step S116, between the grindstone 21a for groove grinding and the probe head 22b based on the relative distances (Xwt, Zwt) of the XZ axis coordinates between the grindstone spindle 21b and the probe shaft 22s. Perform the finishing process by converting the coordinates of. Hereinafter, this relative distance (Xwt, Zwt) may be described as "second relative distance (Xwt, Zwt)". Here, the second relative distance (Xwt, Zwt) is more susceptible to heat as the distance between the grindstone spindle 21b and the probe shaft 22s via the structure increases. Here, the distance via the structure is a distance of a path composed only of a path that always translates to any of the X / Y / Z axes and does not pass through the air. That is, even if the distance via the air is short, if the distance via the structure is long, the thermal deformation becomes large. In particular, in a large-scale grinding apparatus, the distance via the structure is as many as several [m], so that the relative position may be deformed by several tens [μm] even with a slight temperature change. The relative position change caused by this heat causes a large error during coordinate conversion.

On the other hand, after the base position determination process is executed, the base position determination unit 55 performs finishing processing based on the base coordinates (Xb, Zb) calculated based on the first relative distance (Xrt, Zrt). That is, since the coordinate conversion is performed using the first relative distance (Xrt, Zrt) that is not easily affected by heat, it is possible to suppress an error due to thermal deformation.
In the present embodiment, the position reference master is further measured for the outer ring work Wo after the second and subsequent grooves are formed, and the difference between the measurement result and the initial value of the position reference master is calculated. Then, when the calculation result is equal to or less than a preset value, the groove grinding process is executed on the subsequent outer ring work Wo. On the other hand, if it exceeds the specified value, it is determined that it is abnormal, the operation is interrupted, and the operator is notified by an alarm or the like.

In step S106, the groove grinding processing unit 51 determines whether or not it is the execution timing of the truing. Then, when it is determined that it is the execution timing (Yes), the work information measurement command is output to the work information measurement unit 52, and the process proceeds to step S108. If it is determined that the execution timing is not reached, the process proceeds to step S104.
When the process proceeds to step S108, the work information measuring unit measures the first groove bottom diameter Di and the first center coordinates (Xci, Zci) of the outer ring work Wo. After that, the measurement reference coordinate measurement command is output to the measurement reference coordinate measurement unit 53, and the process proceeds to step S110.

In step S110, the measurement reference coordinate measurement unit 53 measures the measurement reference position coordinates (Xr, Zr) using the touch probe 22. After that, the truing execution command is output to the truing processing unit 54, and the process proceeds to step S112.
In step S112, the grooving processing unit 54 executes the grooving of the grindstone 21a for groove grinding to shift to step S114.

Here, the distance Xwt between the grindstone spindle 21b and the probe shaft 22s and the diameter of the grindstone 21a for groove grinding immediately after replacement are known. At the time of grooving, the groove grinding wheel 21a is positioned and cut with respect to the diamond dresser 41 in consideration of these thermal deformations. Further, the position of the base portion 20 at the time when the truing is completed is represented by the measurement reference position coordinates (Xr, Zr).

In step S114, the truing processing unit 54 outputs a wear measurement command to the measuring instrument 45 of the first truing device 4A to measure the amount of wear ΔXt with respect to the reference position (Xt, Zt) of the truing point Pt. Then, after that, the base position determination command is output to the base position determination unit 55, and the process proceeds to step S116.
In step S116, the base position determining unit 55 calculates the first relative distance (Xrt, Zrt) at the end of turwing. Further, from the first relative distance (Xrt, Zrt), the first groove bottom diameter Di and the first center coordinates (Xci, Zci), the groove grinding wheel 21a comes into contact with the first groove bottom Db1. The coordinates (Xb, Zb) of the base portion 20 are calculated. As a result, the position of the base portion 20 is corrected. After that, the position determination completion notification is output to the groove grinding processing unit 51, and the process proceeds to step S118.

In step S118, the grooving processing unit 51 determines whether or not the grooving process has been completed, and if it is determined that the grooving process has been completed (Yes), it is determined that the series of processes has been completed and has not been completed. (No) shifts to step S104.
(Work information measurement processing)
Next, the processing procedure of the work information measurement process executed in step S108 will be described.

When the work information measurement process is executed in step S108, first, as shown in FIG. 7, the process proceeds to step S200.
In step S200, the work information measuring unit 52 measures the shape of the groove portion corresponding to the machining point Pg and the groove portion facing the groove portion through the center of the outer ring work Wo by using the touch probe 22. .. After that, the process proceeds to step S202.

Here, the first and second tip spheres 22d and 22f are used for the measurement. In this case, the work information measuring unit 52 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and first, the first and second tip balls 22d and 22f used for measurement are groove portions to be measured. Move to the unmeasured Z-axis coordinate position on the front.
In the first embodiment, since the processing target is the outer ring work Wo, the groove portions to be measured are a pair of groove portions located at opposite positions. In this case, at the same time, one of the pair of groove portions to be measured faces the first tip sphere 22d, and the other faces the second tip sphere 22f.

Once the Z-axis coordinate position is determined, the first tip sphere 22d or the second tip sphere 22f of the probe head 22b is then brought into contact with the surface of the groove portion to be measured. Specifically, the work information measuring unit 52 drives and controls the X-axis drive motor 28M to move the touch probe 22 in the X-axis direction. Then, the first tip sphere 22d or the second tip sphere 22f is brought into contact with the surface of the groove portion to be measured.

Subsequently, the work information measuring unit 52 acquires the motor rotation angle positions θmx and θmx at the contact positions from the X-axis encoder 28E and the Z-axis encoder 25E. Then, the acquired motor rotation angle positions θmx and θmx are converted into the X-axis coordinate value and the Z-axis coordinate value of the work coordinate system by referring to the conversion table stored in advance in the storage device 70, for example, and a set of these. Is stored in the RAM 62.

The groove shape is measured by repeating the above series of measurement processes while changing the Z-axis coordinates within the range necessary for measuring the shape of the groove portion.
In step S202, in the work information measuring unit 52, the first and second groove bottoms Db1 and Db2 of the first and second groove bottoms Db1 and Db2 are obtained based on the groove shape information (coordinate information) of the pair of opposite groove portions measured in step S200. The groove bottom coordinates (X1, Z1) and (X2, Z2) of are specified. Then, the first groove bottom diameter Di (= X1-X2) is calculated from the specified first and second groove bottom coordinates (X1, Z1) and (X2, Z2). After that, the specified first and second groove bottom coordinates (X1, Z1) and (X2, Z2) and the calculated first groove bottom diameter Di are stored in the RAM 62, and the process proceeds to step S204.

In step S204, in the work information measuring unit 52, the outer ring work is obtained from the first groove bottom diameter Di calculated in step S202 and the Z-axis coordinates of the first and second groove bottoms Db1 and Db2 stored in the RAM 62. The first center coordinates (Xci, Zci) of Wo are calculated. After that, the calculated first center coordinates (Xci, Zci) are stored in the RAM 62, a series of processes are completed, and the original process is restored.

(Base position determination process)
Next, the processing procedure of the base position determination process executed in step S116 will be described.
When the base position determination process is executed in step S116, first, as shown in FIG. 8, the process proceeds to step S300.
In step S300, the base position determining unit 55 calculates the first relative distance (Xrt, Zrt) at the end of turwing. After that, the process proceeds to step S302.

Specifically, the base position determining unit 55 is based on the reference position coordinates (Xt, Zt) of the truing point Pt and the amount of wear ΔXt stored in the RAM 62, and the coordinates (Xt + ΔXt, Zt) of the truing point Pt at the end of the truing. ) Is calculated. Subsequently, from these coordinates (Xt + ΔXt, Zt) and the measurement reference position coordinates (Xr, Zr), the first relative distance (Xrt, Zrt) = (Xr) at the end of turwing according to the above equations (1) and (2). -(Xt + ΔXt), Zr-Zt) is calculated.

In step S302, the base position determination unit 55 calculates the base coordinates (Xb, Zb). After that, the calculated base coordinates (Xb, Zb) are stored in the RAM 62, the series of processing is completed, and the original processing is restored.
Specifically, the base position determining unit 55 has the first relative distance (Xrt, Zrt) calculated in step S300, the first groove bottom diameter Di stored in the RAM 62, and the first center coordinates (Xci, Zci). ), And the base coordinates (Xb, Zb) are calculated according to the above equations (3) and (4).

(motion)
Next, an operation example of the first grinding device 1A of the first embodiment will be described with reference to FIGS. 1 to 8 and with reference to FIGS. 9 to 12.
It is assumed that the grinding start command of the outer ring work Wo is input to the first control device 5A via the input device 74. As a result, the first control device 5A first reads the target groove shape data and the processing condition data stored in the storage device 70 into the RAM 62. Then, based on the read data, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled, and the groove grinding grindstone 21a is placed in the vicinity of the truing point Pt of the first truing device 4A (however, the Z axis). The coordinates move to the grooving start position).

Next, the first control device 5A drives and controls the grindstone spindle motor 21d to rotate the grindstone 21a for groove grinding at a preset rotational speed for trueing. Subsequently, the first control device 5A drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and moves the groove grinding grindstone 21a to the grooving point Pt at the cutting speed for turwing in the X-axis direction. As it moves (cuts), it moves in the Z-axis direction at the feed rate for truing. As a result, the grindstone surface of the grindstone 21a for groove grinding is formed into a desired shape.

Next, the first control device 5A fixes and supports the outer ring master work Wom on the work support member 32 of the work support portion 3 by a work exchange mechanism (not shown). Then, the first control device 5A drives and controls the grindstone spindle motor 21d to rotate the grindstone 21a for groove grinding at a preset rotation speed for groove grinding.
Subsequently, the first control device 5A drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M to move the groove grinding unit 21 and support the grindstone surface of the rotating groove grinding grindstone 21a. The master work Wom for the outer ring, which is fixedly supported by the member 32, moves to the groove forming position on the inner peripheral surface and cuts with a preset depth of cut. As a result, a groove is formed at the contact position of the groove grinding wheel 21a of the master work Wom for the outer ring. The first control device 5A drives and controls the work rotation motor 35 to rotate the outer ring master work worm by a preset rotation angle to form a groove on the inner peripheral surface of the outer ring master work worm.

Subsequently, the first control device 5A uses the touch probe 22 to measure the shape of the groove formed on the inner peripheral surface of the master work worm for the outer ring. As a result, when the groove shape information of the master work Wom for the outer ring is obtained, the first control device 5A then sets the target groove shape based on the measured groove shape information and the target groove shape data read into the RAM 62. The amount of deviation of the formed groove shape is calculated. Then, the calculated deviation amount is stored in the RAM 62 as a correction value.

When the correction value measurement process is completed, the first control device 5A fixes and supports the outer ring work Wo to be processed first to the work support member 32 by a work exchange mechanism (not shown). Then, the first control device 5A measures the position reference master with the probe head 22b for the outer ring work Wo to be processed first.
Specifically, the first control device 5A drives and controls the Z-axis drive motor 25M, moves the tip ball 22f of the probe head 22b in the Z-axis direction, and moves the outer ring work Wo in the Z-axis direction. Measure the upper end position and the lower end position. Next, the first control device 5A drives and controls the X-axis drive motor 28M to move the tip ball 22f of the probe head 22b in the X-axis direction to determine the contact position with the work support member 32. Measure. Then, these measured position information are stored in the RAM 62 as the initial value of the position reference master.

Next, in the first control device 5A, the groove grinding portion 21 roughly grinds the inner peripheral surface of the outer ring work Wo to form a groove. Further, the first control device 5A drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and uses the touch probe 22 to measure the shape of the groove formed in the outer ring work Wo.
Subsequently, the first control device 5A has various dimensions such as a diameter and various dimensions such as an elliptical amount and an inclination error based on the measured groove shape information and the target groove shape data and the correction value stored in the RAM 62. Calculate the error. Then, the first control device 5A stores the calculated various dimensions and various dimensional errors in the RAM 62.

After that, the first control device 5A calculates various correction values such as correction values for posture correction of the groove grinding unit 21 and the remaining groove allowance based on various dimensions and various dimensional errors stored in the RAM 62.
Then, the first control device 5A controls various motors based on various correction values to correct the posture of the machine, and processes the remaining portion of the groove formed in the outer ring work Wo. That is, finishing is performed. At this time, the coordinate conversion between the groove grinding wheel 21a and the probe head 22b is performed using the second relative distance (Xwt, Zwt).

Subsequently, with respect to the second and subsequent outer ring work Wo, the first control device 5A first drives and controls the grindstone spindle motor 21d, the X-axis drive motor 28M, and the Z-axis drive motor 25M to grind the groove. The inner peripheral surface of the outer ring work Wo is roughly ground by the portion 21 to form a groove. Next, the position reference master is measured with respect to the outer ring work Wo after the groove grinding process by the touch probe 22.

Further, the difference value between the position reference master measured value and the previously measured position reference master initial value is calculated, and the calculated difference value and the specified value are compared. Then, when it is determined that the difference value is less than or equal to the specified value, the measurement process of the position information, the calculation process of various dimensions and various dimensional errors, the calculation process of various correction values and the remaining groove margin, and the finishing process are continued in the same manner as described above. Carry out the process.
After that, the same process as described above is repeated to sequentially form grooves on the inner peripheral surface of the outer ring work Wo.

On the other hand, if it is determined that the difference value between the position reference master measured value and the position reference master initial value exceeds the specified value, it is considered that there is an abnormality and the subsequent operation is stopped, and the operator is notified by an alarm device (not shown). Notify that there was an abnormality.
When the abnormality is not detected and the grooving process is repeated, the first control device 5A determines whether or not the timing at which grooving is required is reached during the grooving process. This is determined from, for example, the number of groove grinding operations, the continuous grinding time, and the like.

When the first control device 5A determines that the timing at which truing is required is reached, the first control device 5A first measures the work information on the outer ring work Wo after grooving by using the touch probe 22.
Specifically, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled, and for example, as shown in FIG. 9A, a touch probe 22 is used to form a groove on the Pg side of the machining point. The shape of the first groove portion D1 and the shape of the second groove portion D2, which is a groove portion facing the first groove portion D1, are measured. That is, the first control device 5A performs a process of bringing the second tip sphere 22f of the touch probe 22 into contact with the surface of the first groove D1 to acquire the coordinate information of the groove surface along the first groove D1. Repeat while changing the Z-axis coordinate position. Similarly, the process of bringing the first tip sphere 22d of the touch probe 22 into contact with the surface of the second groove D2 to acquire the coordinate information of the groove surface while changing the Z-axis coordinate position along the second groove D2. Repeat.

The first control device 5A has the first groove bottom coordinates (X1,) of the first groove bottom portion Db1 based on the measured shape information of the first groove portion D1 and the measured shape information of the second groove portion D2. Z1) and the second groove bottom coordinates (X2, Z2) of the second groove bottom portion Db2 are specified.
Subsequently, the first groove bottom diameter Di (= X1-X2) is calculated based on the first and second groove bottom coordinates (X1, Z1) and (X2, Z2). Further, based on the first groove bottom diameter Di, the first groove bottom coordinates (X1, Z1) and the second groove bottom coordinates (X2, Z2), "Xci = X1-Di / 2" and "Zci = Z1". = Z2 ”, the first center coordinates (Xci, Zci) are calculated. The first control device 5A stores the calculated first groove bottom diameter Di and the first center coordinates (Xci, Zci) in the RAM 62.

Subsequently, the first control device 5A measures the measurement reference position coordinates (Xr, Zr).
Specifically, the first control device 5A drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and uses, for example, the touch probe 22 as shown in FIG. 9B. Measurement point Measure the reference position coordinates. Here, the measurement reference position coordinates (Xr, Zr) are measured by bringing the second tip sphere 22f of the touch probe 22 into contact with the measurement point Pm and acquiring the coordinate information of the contact position.

Subsequently, the first control device 5A performs the grooving of the grindstone 21a for grooving in the same manner as in the first grooving before the grooving. That is, the first control device 5A controls various motors, for example, as shown in FIG. 9C, in a state where the groove grinding grindstone 21a is rotated at the rotation speed for turwing, and the notch for turwing is cut. It moves in the X-axis direction at a speed and moves in the Z-axis direction at a feeding speed for turwing. As a result, the grindstone surface of the grindstone 21a for groove grinding is reshaped.

After the completion of the truing, the first control device 5A outputs a measurement command of the amount of wear ΔXt from the reference position (Xt, Zt) of the truing point Pt to the measuring instrument 45 of the first truing device 4A. As a result, the measuring instrument 45 measures, for example, the position of the truing point Pt after being worn by the truing, as shown in the lower figure of FIG. 9D. Then, the difference ΔXt from the reference position before truing shown in the upper figure of FIG. 9D is calculated. The amount of wear ΔXt measured by the measuring device 45 is input to the first control device 5A via an electric cable (not shown).

As shown in FIG. 10, the first control device 5A has a portion (truing) in contact with the first groove bottom portion Db1 of the outer ring work Wo of the groove grinding wheel 21a at the end of grooving from the input amount of wear ΔXt. The coordinates (Xt + ΔXt, Zt) of the portion in contact with the truing point Pt at the end are calculated.
Subsequently, the first control device 5A has the coordinates (Xt + ΔXt, Zt) of the portion of the outer ring work Wo of the grindstone 21a for groove grinding at the end of the truing that comes into contact with the first groove bottom Db1, and the measurement reference position coordinates (Xr). , Zr) and the relative distance is calculated.

Specifically, as shown in FIG. 10, the first control device 5A calculates the relative distance Xrt of the X-axis coordinates as "Xrt = Xr- (Xt + ΔXt)" according to the above equation (1), and calculates the above equation (Xt + ΔXt). According to 2), the relative distance Zrt of the Z-axis coordinates is calculated as "Zrt = Zr-Zt".
Then, the first control device 5A is based on the calculated first relative distance (Xrt, Zrt), the first groove bottom diameter Di, and the first center coordinates (Xci, Zci), and the base coordinates (Xb, Zci). Zb) is calculated.

Specifically, the first control device 5A sets the X-axis coordinate Xb of the position corresponding to the X-axis coordinate Xr of the measurement point Pm at the end of the truing of the base portion 20 to "Xb = Xci + Xrt + Di /" according to the above equation (3). 2 ”is calculated. Further, according to the above equation (4), the Z-axis coordinate Zb at the position corresponding to the Z-axis coordinate Zr of the measurement point Pm at the end of the truing of the base portion 20 is calculated as “Zb = Zci + Zrt”.

That is, as shown in FIG. 11, the base coordinates (Xb, Zb) correspond to the position of the measurement point Pm of the measurement reference 42 when the grindstone 21a for groove grinding at the end of growing is in contact with the growing point Pt. It becomes the coordinates of the position.
In this way, the position of the base portion 20 when the grindstone 21a for groove grinding comes into contact with the first groove bottom portion Db1 is calculated from the relative distance between the truing point Pt and the measurement point Pm, which have a relatively small thermal effect. I made it. As a result, the relative position change due to the thermal effect can be changed as compared with the case where the second relative distance (Xwt, Zwt), which is the relative distance between the grindstone spindle 21b and the probe shaft 22s, which have a relatively large thermal effect, is used. It becomes possible to suppress.

In the finishing process after determining the base coordinates, the first control device 5A has a target groove bottom diameter Dif with respect to the current first groove bottom diameter Di, for example, as shown in FIG. 9E. In addition, by relatively moving (Dif-Di) / 2 from the base coordinates (Xb, Zb) to process the outer ring work Wo, it is possible to finish the work W to a desired size.
After that, the groove shape is measured by the touch probe 22 for each outer ring work Wo until it is time to execute the next truing, and based on the measured groove shape data, the first groove bottom diameter Di and the first groove bottom diameter Di The center coordinates (Xci, Zci) are calculated. Then, using these calculated values and the first relative distance (Xrt, Zrt) calculated this time, the base coordinates (Xb, Zb) when the grindstone 21a for groove grinding comes into contact with the first groove bottom Db1 are obtained. After determining, the same finishing process as described above is performed.

In addition, the first relative distance (Xrt, Zrt) is calculated by executing the above series of processes each time the truing is executed. Then, the base coordinates (Xb, Zb) are determined from the calculated first relative distance (Xrt, Zrt), and the same finishing processing as described above is performed.
On the other hand, when the base position determination process using the first relative distance (Xrt, Zrt) between the truing point Pt and the measurement point Pm of the measurement reference 42 is not performed, the groove grinding wheel 21a is the first groove bottom portion. An example of a method of obtaining the base coordinates (Xb, Zb) when contacting Db1 will be described.

First, the shape of the first groove D1 and the shape of the second groove D2 of the outer ring work Wo are measured by using the touch probe 22. Further, the first groove bottom diameter Di and the first center coordinates (Xci, Zci) are calculated based on the measured shape information.
Next, with the center position of the tip portion of the probe shaft 22s as the position of the base portion 20, the positions of the first center coordinates (Xci, Zci) and the center coordinates of the XZ axis of the third tip sphere 22h are aligned. The coordinates at this time are set to the base coordinates (Xb, Zb) = (Xci, Zci).

Further, where the grindstone diameter of the grindstone 21a for groove grinding is Dg, the position of the base portion 20 when the grindstone 21a for groove grinding comes into contact with the first groove bottom portion Db1 (that is, the center position of the XZ axis of the third tip ball 22h). ) Can be obtained from the following equations (5) and (6) using the relative distances (Xwt, Zwt) between the grindstone spindle 21b and the probe shaft 22s.
Xb = Xci + (Xwt-Dg / 2) + Di / 2 ... (5)
Zb = Zci + Zwt ・ ・ ・ (6)
Here, the first center coordinates (Xci, Zci) and the first groove bottom diameter Di, which are measured values, are values that are not affected by thermal deformation. On the other hand, as shown by the bidirectional arrow line in (1) in FIG. 12, the distance between the grindstone spindle 21b and the probe shaft 22s via the structure is long, and in particular, a large grinding machine (large grinding machine). ) Etc., it becomes a number [m]. In addition, there is a first heat generating source Hs1 caused by the grindstone spindle motor 21d in the structure in the path (1) in the figure.

Further, as shown by the bidirectional arrow line in (2) in FIG. 12, the distance between the grindstone 21a for grooving at the time of grooving and the diamond dresser 41 of the first grooving device 4A via the structure is established. Is long, and in particular, it can be several [m] in a large grinding machine or the like. In addition, under the influence of heat, the grindstone diameter Dg changes by twice the relative positional relationship between the grindstone 21a for groove grinding and the diamond dresser 41. Further, as shown in FIG. 12, in the path (2) in the figure, a second heat generating source Hs2 due to groove processing at the processing point Pg and a work rotation motor 35 as factors are factors. There are 3 heat sources Hs3.

From the above, the second relative distances (Xwt, Zwt) and the grindstone diameter Dg are distances and dimensions that are easily affected by heat, and errors are likely to occur due to thermal deformation of the structure.
On the other hand, as shown by the bidirectional arrow line in (3) in FIG. 12, the distance between the measurement reference 42 and the diamond dresser 41 of the first truing device 4A via the structure is short. Moreover, since there are few heat sources in the vicinity, the component is in a thermally stable position. That is, the first relative distance (Xrt, Zrt) between the measurement point Pm of the measurement reference 42 and the truing point Pt of the diamond dresser 41 is unlikely to cause an error due to thermal deformation of the structure.

Here, the grindstone 21a for groove grinding corresponds to a rotary grindstone, the first truing device 4A corresponds to a truing portion, the dresser base 40 corresponds to a base, and the diamond dresser 41 corresponds to a dresser.
Further, the groove grinding unit 51 corresponds to the grinding unit, the work information measuring unit 52 corresponds to the work shape measuring unit, and the measuring instrument 45 corresponds to the trueing point coordinate measuring unit.

(Action and effect of the first embodiment)
The first grinding device 1A according to the first embodiment is configured such that the position of the machining point Pg is located on the truing point Pt side with the grindstone spindle 21b interposed therebetween when viewed from the Y-axis direction. In addition, a groove grinding unit 21 having a grindstone spindle 21b, a grindstone for groove grinding 21a attached to the tip of the grindstone spindle 21b, and a grindstone spindle motor 21d for rotationally driving the grindstone spindle 21b is provided. Further, a work support member 32 that fixedly supports the work W, a table 31 that rotatably supports the work support member 32 in an axial direction parallel to the grindstone spindle 21b via the work rotation spindle 33, and a work rotation. A work support portion 3 having a work rotation motor 35 for rotationally driving the work spindle 33 is provided. Further, a touch probe 22 having a probe shaft 22s and a stylus 22t provided at the tip of the probe shaft 22s is provided. Further, it includes a base portion 20 that fixedly supports the groove grinding portion 21 and the touch probe 22 in parallel with the axis, and a measurement reference 42 that is a position reference of the touch probe 22. Further, the dresser base 40 is provided with a first truing device 4A having a dresser base 40 and a diamond dresser 41 for truing the groove grinding grindstone 21a provided on the side of the dresser base 40 facing the work support portion 3. Further, a moving mechanism that moves the first and second base portions 23 and 26 to the grinding position of the work W, the truing position of the grindstone 21a for groove grinding, the measurement position of the shape of the work W, and the measurement position of the measurement reference 42. It has a part. This movement mechanism unit serves as a mechanism unit for moving the first base unit 23 of the base unit 20 in the Z-axis direction, such as a Z-axis drive motor 25M, a first left linear motion guide device 24L, and a first right. A linear motion guide device 24R and a first ball screw device 25 are provided. Further, this moving mechanism unit is a mechanism unit for moving the second base unit 26 of the base unit 20 in the X-axis direction, such as an X-axis drive motor 28M, a second left linear motion guide device 27L, and a second. The right linear motion guide device 27R and the second ball screw device 28 are provided.

In the first grinding device 1A according to the first embodiment, the groove grinding unit 51 drives the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M. Controlled, the groove grinding grindstone 21a that rotates at a preset rotation speed for groove grinding is brought into contact with the work W fixedly supported by the work supporting member 32, and the work W is ground. The work information measuring unit 52 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and the stylus 22t of the touch probe 22 is fixedly supported by the work support portion 3 on the work W after grinding. The work W is brought into contact with each other to measure the shape of the work W. The measurement reference coordinate measurement unit 53 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M to bring the stylus 22t of the touch probe 22 into contact with the measurement reference 42, and the measurement point Pm of the measurement reference 42. Performs a process of measuring the position coordinates (Xr, Zr) of. The grooving processing unit 54 drives and controls the grindstone spindle motor 21d, the X-axis drive motor 28M, and the Z-axis drive motor 25M to drive and control the groove grinding grindstone 21a that rotates at a preset rotation speed for grooving. The groove grinding grindstone 21a is trued by contacting the truing point Pt of the diamond dresser 41 of the truing device 4A. The measuring instrument 45 of the first truing device 4A measures the position coordinates (Xt, Zt) of the truing point Pt.

Here, the measurement reference 42 and the diamond dresser 41 are the first relative distances between the position coordinates (Xr, Zr) of the measurement point Pm due to the thermal influence and the position coordinates (Xt, Zt) of the truing point Pt. The distances (Xrt, Zrt) are arranged in a positional relationship within a range that satisfies the preset target machining accuracy. Specifically, in the first embodiment, the first truing device 4A is arranged at a position as far as possible from the heat source, for example, and the measurement reference 42 is the dresser base 40 of the first truing device 4A. It is provided at the top. More specifically, in the measurement reference 42, for example, when the frame of the dresser base 40 is made of iron and the target processing accuracy is set to 5 [μm] or less, the distance from the diamond dresser 41 via the structure is 41 [cm]. ] It is provided at the following positions.

Further, the base position determining unit 55 represents the position coordinates of the base unit 20 at the end of turwing by the position coordinates (Xr, Zr) of the measurement reference 42. In addition, the first relative distance (Xrt, Zrt) between the position coordinates (Xr, Zr) of the measurement reference 42 and the position coordinates (Xt, Zt) of the truing point Pt measured by the measuring instrument 45 at the end of the truing, and the work. Based on the shape information of the work W measured by the information measuring unit 52, the position coordinates (Xb, Zb) of the base portion 20 corresponding to the representative position coordinates when the groove grinding grindstone 21a comes into contact with the work W during grinding. ) Is determined. The groove grinding unit 51 finishes the work W based on the position coordinates (Vb, Zb) of the base portion determined by the base position determining unit 55.

Further, the work W is an annular member (work W for outer ring, work Wi for inner ring) that constitutes a raceway ring of a rolling bearing. Then, the groove grinding process section 51 of the first embodiment performs a groove grinding process for grinding a groove serving as a rolling path of the rolling element on the inner peripheral surface of the outer ring work Wo. The work information measuring unit 52 measures the shapes of the first and second groove portions D1 and D2 facing each other through the center of the outer ring work Wo of the groove formed on the inner peripheral surface of the outer ring work Wo. In addition, the groove bottom portion is based on the coordinates (X1, Z1) of the first groove bottom portion Db1 and the coordinates (X2, Z2) of the second groove bottom portion Db2 specified from the shapes of the first and second groove portions D1 and D2. The process of calculating the first groove bottom diameter Di and the first center coordinates (Xci, Zci) of the outer ring work Wo, which are the linear distances between them, is performed. The base position determination unit 55 determines the first relative distance (Xrt, Zrt) between the position coordinates (Xr, Zr) of the measurement reference 42 and the position coordinates (Xt, Zt) of the truing point Pt at the end of the truing, and the first. Based on the groove bottom diameter Di and the first center coordinates (Xci, Zci) of the above, the representative position when the groove grinding grindstone 21a comes into contact with the first groove bottom portion Db1 of the outer ring work Wo during groove grinding. The position coordinates (Xb, Zb) of the base portion 20 corresponding to the coordinates are determined.

Specifically, the first relative distance (Xrt, Zrt) between the coordinates (Xr, Zr) of the measurement point Pm of the measurement reference 42 and the coordinates (Xt, Zt) of the truing point Pt at the end of the truing, and the first. From the groove bottom diameter Di and the first center coordinates (Xci, Zci) of the outer ring work Wo, the coordinates (Xb, Zb) of the base portion 20 corresponding to the representative position coordinates are set in the above equations (3) and (3). Calculate according to 4).

With the above configuration, a first relative distance (Xrt, Zrt) that is less susceptible to heat is used when determining the position coordinates (Xb, Zb) of the base portion 20 as compared with the conventional positioning method. Therefore, relatively stable processing becomes possible. Further, it is possible to suppress the influence of thermal deformation only by changing the positional relationship between the truing point Pt and the measurement reference 42 regardless of the distance via the structure, that is, the size of the grinding device. This effect is due to the large difference between the first relative distance Xrt and the second relative distance Xwt in the X-axis direction and the difference between the first relative distance Zrt and the second relative distance Zwt in the Z-axis direction. It becomes remarkable in the grinding machine. Further, since it is not necessary to consider the coefficient of linear expansion of the structural material, there are no restrictions on the material as compared with the conventional case. Further, since it is not necessary to perform complicated thermal deformation control, it is not necessary to upgrade the equipment, and the cost for that is not required. That is, it is possible to perform positioning that suppresses the influence of thermal deformation at a simpler and lower cost than in the past.
(Second Embodiment)
(Constitution)
In the second embodiment, in the first grinding device 1A of the first embodiment, the second truing device 4B and the second control device 5B are replaced with the first truing device 4A and the first control device 5A. The difference is that Further, in the first grinding device 1A of the first embodiment, the machining point Pg is on the same side as the truing point Pt with the grindstone spindle 21b interposed therebetween when viewed from the Y-axis direction. On the other hand, in the second grinding device 1B of the second embodiment, the machining point Pg is on the opposite side of the grinding wheel spindle 21b from the truing point Pt when viewed from the Y-axis direction. That is, since the contact point at the time of grooving and the contact point at the time of machining of the grindstone 21a for groove grinding are opposite with each other of the grindstone spindle 21b, the coordinate conversion is performed using the first relative distance (Xrt, Zrt). In this case, it is necessary to consider the grindstone diameter of the grindstone 21a for groove grinding. However, since the grindstone diameter changes twice as much as the change in the positional relationship between the truing point Pt and the groove grinding grindstone 21a, it is necessary to correct the grindstone diameter. Therefore, the second grinding device 1B of the second embodiment is different from the first embodiment in that it has a means for correcting the diameter of the grindstone.

Hereinafter, the same components as those in the first embodiment will be designated by the same reference numerals, description thereof will be omitted as appropriate, and different points will be described in detail.
As shown in FIG. 13, the second grinding device 1B according to the second embodiment includes a grinding measuring section 2, a work support section 3, a second growing device 4B, and a second control device 5B. ing.
The work W illustrated in FIG. 13 is an inner ring work Wi of a ball bearing, and in order to form a groove on the outer peripheral surface of the inner ring, the inner ring work Wi is magnetically applied to the upper end of the cylindrical work support member 32. It is adsorbed and fixedly supported.

As shown in FIGS. 13 and 14, the second truing device 4B includes a dresser base 40, a diamond dresser 41, a measurement reference 42, a sensor support portion 43, and a proximity sensor 44.
The sensor support portion 43 has a first support portion 43a and a second support portion 43b connected to the first support portion 43a. One end of the first support portion 43a is fixed to the surface of the dresser base 40 on the diamond dresser 41 side, and the first support portion 43a is made of, for example, a prismatic member made of a low-line expansion alloy that extends horizontally from one end side toward the work support portion 3. It is configured. The second support portion 43b is composed of a prismatic member made of a low-line expansion alloy that extends vertically upward from the other end portion (tip portion) of the first support portion 43a.

The proximity sensor 44 is a sensor provided at the upper end of the second support portion 43b (a position facing the tsuruing point Pt in the X-axis direction) and detects an object approaching within the proximity detection boundary DP. For example, an air micro sensor, an AE (Acoustic Emission) sensor, and the like are applicable. Here, the proximity detection boundary DP is a boundary between a range in which the proximity sensor 44 can detect an object close to itself and a range in which it cannot be detected. In the second embodiment, as shown in FIG. 14, the proximity sensor 44 detects the groove grinding wheel 21a approaching from the diamond dresser 41 side to within the proximity detection boundary DP.

(Hardware configuration of the second control device 5B)
The hardware configuration of the second control device 5B is the same as the hardware configuration of the first control device 5A of the first embodiment.
(Functional configuration of the second control device 5B)
The second control device 5B has a groove grinding processing unit 51, a work information measurement unit 52, a measurement reference coordinate measurement unit 53, a growing processing unit 54, and a base position determination unit 55 as the second functional configuration unit 50B. And a grindstone diameter measuring unit 56.

In the groove grinding processing unit 51 of the second embodiment, at the execution timing of the second truing after the power is turned on, the coordinates (Xow, Xow, Zow) is measured. Then, the measured coordinates (Xow, Zow) of the center point GSc are stored in the RAM 62. After that, the work information measurement command is output to the work information measurement unit 52.

The groove grinding unit 51 of the second embodiment further performs groove processing using the groove grinding wheel 21a after executing the second truing in response to the notification of the completion of calculation of the reference wheel diameter from the grindstone diameter measuring unit 56. Execute the process. In addition, in response to the position determination completion notification from the base position determination unit 55, the groove machining process is executed using the groove grinding wheel 21a after executing the third and subsequent truing.
The work information measuring unit 52 of the second embodiment uses the touch probe 22 in response to the work information measurement command from the groove grinding processing unit 51, and the groove portion of the inner ring work Wi after the groove grinding process, and the back surface thereof. Measure the distance between the groove bottom and the opposite groove. In addition, the coordinates of the center position Rco of the inner ring work Wi are measured.

Here, in the second embodiment, as shown in FIG. 13, the third groove bottom portion Db3, which is the groove bottom portion of the groove portion on the processing point Pg side of the groove formed on the inner ring work Wi after the groove grinding process. The second groove bottom diameter Do, which is the distance between this and the fourth groove bottom portion Db4, which is the groove bottom portion of the groove portion facing the back surface, is measured. In addition, the second center coordinates (Xoc, Zoc), which are the coordinates of the center position Rco of the inner ring work Wi, are measured.

Specifically, the work information measuring unit 52 first uses the touch probe 22 in response to the work information measuring command input from the groove grinding processing unit 51 to form the groove shape of the inner ring work Wi after the groove grinding process. To measure. Similar to the case of the outer ring work Wo of the first embodiment, this process is executed by driving and controlling the work rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M.

Based on the measurement result of the groove shape, the work information measuring unit 52 of the second embodiment has the deepest part of the groove with respect to the two groove portions facing the back surface of the inner ring work Wi, that is, the processing point Pg side and the back surface facing each other. The third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4), which are the coordinates of the third and fourth groove bottoms Db3 and Db4 on the side, are specified. In addition, Z3 = Z4. Then, based on the specified third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4), the distance between the groove bottoms (second groove bottom diameter) Do and the center position Rco of the inner ring work Wi The second center coordinates (Xoc, Zoc), which are the coordinates, are calculated.

When the work information measuring unit 52 of the second embodiment finishes the measurement of the second groove bottom diameter Do and the second center coordinates (Xoc, Zoc) before the execution timing of the second truing, the grindstone The diameter calculation command is output to the grindstone diameter measuring unit 56.
The measurement reference coordinate measurement unit 53 of the second embodiment uses the touch probe 22 in response to a command from the work information measurement unit 52 before the execution of the truing at the execution timing of the second truing, and uses the measurement reference position. The coordinates (Xr, Zr) are measured. Then, the measured measurement reference position coordinates (Xr, Zr) are stored in the RAM 62. After that, the measurement completion notification is output to the truth processing unit 54. Further, at the third and subsequent execution timings of the truing, the measurement reference position coordinates (Xr, Zr) are measured by using the touch probe 22 in response to a command from the truing processing unit 54 before the execution of the truing. Then, the measured measurement reference position coordinates (Xr, Zr) are stored in the RAM 62. After that, the truing execution command is output to the truing processing unit 54.

The grindstone diameter measuring unit 56 has the coordinates (Xow, Zow) of the center point GSc of the grindstone 21a for groove grinding and the second groove stored in the RAM 62 in response to the grindstone diameter calculation command from the work information measuring unit 52. From the bottom diameter Do and the second center coordinates (Xoc, Zoc), the first grindstone diameter Dwn at the completion of grooving is calculated according to the following equation (7).
Dwn = 2 × (Xow-Xoc) -Do ... (7)
The grindstone diameter measuring unit 56 stores the calculated first grindstone diameter Dwn at the completion of grooving in the RAM 62, and then outputs a measurement reference coordinate measurement command to the measurement reference coordinate measuring unit 53.

The grindstone diameter measuring unit 56 is further separated from the truing point Pt by a predetermined distance α by using the proximity sensor 44 before the second truing is executed in response to the grindstone feed distance measurement command from the truing processing unit 54. The first grindstone feed distance Xw0, which is the feed distance of the grindstone 21a for groove grinding from the position to the proximity detection boundary DP, is measured. Then, the measured first grindstone feed distance Xw0 is stored in the RAM 62, and the truing execution command is output to the truing processing unit 54.

The grindstone diameter measuring unit 56 first uses the proximity sensor 44 to grind the groove from the truing point Pt to the proximity detection boundary DP after the second truing in response to the reference grindstone diameter measuring command from the truing processing unit 54. The second grindstone feed distance Xw1, which is the feed distance of the grindstone 21a, is measured. Next, the first grindstone diameter Dwn, the first grindstone feed distance Xw0 and the second grindstone feed distance Xw1 at the time of completion of the groove machining stored in the RAM 62, and the predetermined distance α stored in advance in the ROM 64 or the storage device 70. And the reference grindstone diameter Dw0 is calculated according to the following formula (8) from the depth of cut A0 at the time of the second truing.

Dw0 = Dwn-2 × (Xw1-Xw0-A0) ... (8)
The calculation process of the above equation (8) is the following equations (8a) to (8d) (see FIG. 20 (a)).
Dw0 = Dwn-2 × (A0-α) ・ ・ ・ (8a)
Xw1 + Dwn-2 × (A0-α) = Xw0 + Dwn + a ... (8b)
α = Xw0-Xw1 + 2A0 ... (8c)
Dw0 = Dwn-2 × (A0- (Xw0-Xw1 + 2A0)) ... (8d)
By rearranging the above equation (8d), the above equation (8) is derived.

Then, the calculated reference grindstone diameter Dw0 is stored in the RAM 62. After that, a notification of completion of calculation of the reference grindstone diameter is output to the groove grinding processing unit 51.
The grindstone diameter measuring unit 56 first uses the proximity sensor 44 to determine the feed distance of the grindstone 21a for groove grinding from the truing point Pt to the proximity detection boundary DP in response to the grindstone diameter measuring command from the growing processing unit 54. The third grindstone feed distance Xw2 is measured. Then, the distance difference ΔXw, which is the difference between the second grindstone feed distance Xw1 and the third grindstone feed distance Xw2, is calculated. Next, the measuring instrument 45 of the first truing device 4A is made to measure the current wear position T1 of the truing point Pt of the diamond dresser 41. Then, the wear difference ΔT, which is the difference between the reference wear position T0 (described later) and the measured wear position T1, is calculated. Subsequently, from the reference grindstone diameter Dw0 stored in the RAM 62 and the calculated wear difference ΔT and distance difference ΔXw, the second grindstone diameter Dw, which is the grindstone diameter in which the error due to thermal deformation is corrected according to the following equation (9). Is calculated. Then, the calculated second grindstone diameter Dw is stored in the RAM 62. After that, the base position determination command is output to the base position determination unit 55.

Dw = Dw0-2 × (ΔXw + ΔT) ... (9)
The truing processing unit 54 of the second embodiment responds to the measurement completion notification from the measurement reference coordinate measurement unit 53 to the measuring instrument 45 of the second truing device 4B before executing the second truing, and the diamond dresser 41 is attached to the measuring instrument 45. The reference wear position T0 of the true truing point Pt is measured. Then, the measured reference wear position T0 is stored in the RAM 62, and the grindstone feed distance measurement command is output to the grindstone diameter measuring unit 56.

Further, the truing processing unit 54 of the second embodiment performs the second truing of the grindstone 21a for groove grinding in the same procedure as that of the first embodiment in response to the truing execution command from the grindstone diameter measuring unit 56. .. After that, the reference grindstone diameter measurement command is output to the grindstone diameter measuring unit 56.
Further, the truing processing unit 54 of the second embodiment executes truing in response to a truing execution command from the measurement reference coordinate measurement unit 53 at the third and subsequent truing execution timings. After that, the grindstone diameter measurement command is output to the grindstone diameter measuring unit 56.

The base position determining portion 55 of the second embodiment determines the position of the base portion 20 when the grindstone 21a for groove grinding and the third groove bottom portion Db3 on the processing point Pg side of the inner ring work Wi come into contact with each other.
Specifically, the base position determination unit 55 receives the coordinates (Xt, Zt) of the truing point Pt at the end of the truing stored in the RAM 62 in response to the base position determination command from the grindstone diameter measurement unit 56, and the measurement reference. The first relative distance (Xrt, Zrt) is calculated from the position coordinates (Xr, Zr).

Subsequently, from the calculated first relative distance (Xrt, Zrt), the second groove bottom diameter Do, the second center coordinates (Xoc, Zoc), and the second grindstone diameter Dw stored in the RAM 62. Based on the following equations (10) and (11), the base coordinates (Xb, Zb) which are the positions of the base portion 20 when the grindstone 21a for groove grinding and the third groove bottom portion Db3 of the inner ring work Wi come into contact with each other. Is calculated. Then, the calculated base coordinates (Xb, Zb) are stored in the RAM 62.

In this way, the first relative distance (Xrt, Zrt) between the trueing point Pt and the measurement point Pm, which are not easily affected by heat, the second grindstone diameter Dw, which is not affected by heat, and the second groove bottom. By determining the base coordinates from the diameter Do and the second center coordinates (Xoc, Zoc), the error due to thermal deformation is corrected.
Xb = Xoc + Do / 2 + Xrt + Dw ... (10)
Zb = Zoc + Zrt ... (11)
Then, when the base coordinates (Xb, Zb) are determined, the base position determination unit 55 outputs a position determination end notification to the groove grinding process unit 51.

(Groove processing of work Wi for inner ring)
Next, the processing procedure of the groove processing of the inner ring work Wi of the second embodiment will be described with reference to FIG.
When the program is executed by the CPU 60 of the second control device 5B and the groove processing of the inner ring work Wi is started, the process first proceeds to step S400 as shown in FIG.

In step S400, the groove grinding processing unit 51 reads the target groove shape data and the processing condition data corresponding to the model number of the inner ring work Wi to be ground from the storage device 70 into the RAM 62, and proceeds to step S402.
In step S402, the groove grinding processing unit 51 performs groove shape management processing based on the processing condition data read into the RAM 62. After that, the process proceeds to step S404.

Here, in the groove shape management process, the groove grinding wheel 21a is trued into a shape capable of forming the groove shape to be formed by using the second grooving device 4B, and the grooving grindstone 21a is formed. It includes a process of grinding a groove on the peripheral surface of the master work Wim for the inner ring. Further, the groove shape management process includes a process of measuring the position reference master for the outer ring work Wo to be processed first and storing the measured value as the initial value of the position reference master in the RAM 62.

In step S404, the groove grinding process section 51 executes the groove grinding process. After that, the process proceeds to step S406.
Here, in the groove grinding process of the second embodiment, the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled, and first, for the inner ring. A groove is roughly ground on the outer peripheral surface of the work Wi using a grindstone 21a for groove grinding. Subsequently, the work rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled, and the groove shape of the inner ring work Wi is measured by the touch probe 22. Subsequently, a dimensional error is calculated based on this measurement result, and based on the calculated dimensional error, the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M are driven and controlled. Therefore, it is a process of finishing the groove.

At this time, before executing the thermal deformation correction process in step S418, the finish processing is performed by performing coordinate conversion between the groove grinding wheel 21a and the probe head 22b based on the second relative distance (Xwt, Zwt). ..
On the other hand, after the thermal deformation correction processing is executed, the base position determination unit 55 sets the base coordinates (Xb, Zb) calculated based on the second grindstone diameter Dw and the first relative distance (Xrt, Zrt). Based on this, finish processing is performed. That is, since the coordinate conversion is performed using the second grindstone diameter Dw whose dimensional error is corrected by the measurement by the proximity sensor 44 and the first relative distance (Xrt, Zrt) which is not easily affected by heat, thermal deformation occurs. It is possible to suppress the error due to.

In the present embodiment, the position reference master is further measured for the inner ring work Wi after the second and subsequent grooves are formed, and the difference between the measurement result and the initial value of the position reference master is calculated. Then, when the calculation result is equal to or less than the preset predetermined value, the groove grinding process is executed on the subsequent inner ring work Wi. On the other hand, if it exceeds the specified value, it is determined that it is abnormal, the operation is interrupted, and the operator is notified by an alarm or the like.

In step S406, the groove grinding unit 51 determines whether or not it is the trueing execution timing, and if it is determined that it is the execution timing (Yes), the process proceeds to step S408, and if it is determined that it is not (No), the process proceeds to step S408. , Step S410.
When the process proceeds to step S408, the groove grinding processing unit 51 determines whether or not it is the execution timing of the second truing. Then, when it is determined that it is the second execution timing (Yes), the process proceeds to step S410, and when it is determined that it is not (No), the process proceeds to step S412.

When the process proceeds to step S410, the second functional configuration unit 50B executes a reference grindstone diameter measurement process to move to step S414.
On the other hand, when the process proceeds to step S412, the second functional configuration unit 50B executes the thermal deformation correction process and proceeds to step S414.
In step S414, the grooving processing unit 51 determines whether or not the grooving process has been completed, and if it is determined that the grooving process has been completed (Yes), the series of processes has been completed and it has been determined that the grooving process has not been completed. (No) shifts to step S404.

(Reference whetstone diameter measurement process)
Next, a processing procedure of the reference grindstone diameter measurement process executed in step S410 will be described with reference to FIG.
When the reference grindstone diameter measurement process is executed in step S410, the process first proceeds to step S500, as shown in FIG.

In step S500, the groove grinding unit 51 measures the coordinates (Xow, Zow) of the center point GSc of the groove grinding wheel 21a at the completion of the groove processing before executing the second grooving process. Then, the measured center coordinates (Xow, Zow) are stored in the RAM 62. After that, the work information measurement command is output to the work information measurement unit 52, and the process proceeds to step S502.

Here, the grooving processing unit 51 acquires the motor rotation angle positions θmx and θmx when the grooving is completed from the X-axis encoder 28E and the Z-axis encoder 25E. Then, the acquired motor rotation angle positions θmx and θmx are converted into X-axis coordinate values Xow and Z-axis coordinate values Zow of the center point GSc of the groove grinding wheel 21a, and these sets are stored in the RAM 62.
In step S502, the work information measuring unit 52 measures the work information using the touch probe 22 in response to the input of the work information measurement command, and stores the measured work information in the RAM 62. After that, the grindstone diameter calculation command is output to the grindstone diameter measuring unit 56, and the process proceeds to step S504.

Specifically, the work information measuring unit 52 passes through the groove portion corresponding to the machining point Pg and the center of the inner ring work Wi to the groove portion, as in the case of the outer ring work Wo of the first embodiment. Measure the shape of the groove portion facing the back surface. Next, based on the measured groove shape information (coordinate information) of the pair of groove portions facing the back surface, the third and fourth groove bottom coordinates (X3, Z3) of the third and fourth groove bottoms Db3 and Db4 and (X4, Z4) is specified. Further, the second groove bottom diameter Do (= X3-X4) is calculated from the third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4). Then, the second center coordinates (Xoc, Zoc) of the inner ring work Wi are calculated from the third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4) and the second groove bottom diameter Do. ..

In step S504, the grindstone diameter measuring unit 56 receives the input of the grindstone diameter calculation command, and receives the second groove bottom diameter Do, the second center coordinates (Xoc, Zoc), and the center point GSc stored in the RAM 62. From the coordinates (Xow, Zow), the first grindstone diameter Dwn is calculated according to the above equation (7). After that, the calculated first grindstone diameter Dwn is stored in the RAM 62, the measurement reference coordinate measurement command is output to the measurement reference coordinate measurement unit 53, and the process proceeds to step S506.

When the grindstone 21a for groove grinding is the one immediately after replacement, the grindstone diameter measuring unit 56 stores the catalog value previously stored in the ROM 64 or the storage device 70 as the first grindstone diameter Dwn in the RAM 62.
In step S506, the measurement reference coordinate measurement unit 53 measures the measurement reference position coordinates (Xr, Zr) using the touch probe 22 in response to the input of the measurement reference coordinate measurement command. After that, the measured measurement reference position coordinates (Xr, Zr) are stored in the RAM 62, the measurement completion notification is output to the truing processing unit 54, and the process proceeds to step S508.

In step S508, the truing processing unit 54 outputs a wear measurement command to the measuring instrument 45 of the second truing device 4B in response to the input of the measurement completion notification, and measures the reference wear position T0 of the truing point Pt. Let me. Then, the measured reference wear position T0 is stored in the RAM 62, the grindstone feed distance measurement command is output to the grindstone diameter measuring unit 56, and the process proceeds to step S510.

Specifically, the measuring instrument 45 measures the X coordinate Xt0 of the current truing point Pt, and stores this Xt0 in the RAM 62 as the reference wear position T0.
In step S510, the grindstone diameter measuring unit 56 measures the first grindstone feed distance Xw0 using the proximity sensor 44 in response to the input of the grindstone feed distance measurement command. After that, the measured first grindstone feed distance Xw0 is stored in the RAM 62, a truing execution command is output to the truing processing unit 54, and the process proceeds to step S512.

Specifically, the grindstone diameter measuring unit 56 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and first places the grindstone 21a for groove grinding at a position separated by a predetermined distance α from the truing point Pt. Moving. Then, the motor rotation angle position θmx is acquired from the X-axis encoder 28E, converted into an X-axis coordinate value, and the converted X-coordinate value of the first grindstone X-coordinate value Xg1 is stored in the RAM 62. Next, the grindstone diameter measuring unit 56 drives and controls the X-axis drive motor 28M to move the groove grinding grindstone 21a in the negative direction of the X-axis (the X− direction in FIG. 13). Then, the groove grinding wheel 21a is stopped at the position where the proximity sensor 44 first detects the approach of the groove grinding wheel 21a (the position of the proximity detection boundary DP), and the motor rotation angle position θmx is acquired from the X-axis encoder 28E. Then, the acquired motor rotation angle position θmx is converted into an X-axis coordinate value to obtain a second grindstone X coordinate value Xg2.

Subsequently, the grindstone diameter measuring unit 56 calculates the first grindstone feed distance Xw0 by subtracting the second grindstone X coordinate value Xg2 from the first grindstone X coordinate value Xg1 stored in the RAM 62.
In step S512, the truing processing unit 54 executes the truing of the groove grinding grindstone 21a in response to the input of the truing execution command. After that, the grindstone diameter measurement command is output to the grindstone diameter measuring unit 56, and the process proceeds to step S514.

Specifically, the truing processing unit 54 drives and controls the X-axis drive motor 28M to cut the groove grinding grindstone 21a with respect to the truing point Pt of the diamond dresser 41 by the depth of cut A0 to perform truing.
In step S514, the grindstone diameter measuring unit 56 measures the second grindstone feed distance Xw1 using the proximity sensor 44 in response to the input of the grindstone diameter measuring command. After that, the measured second grindstone feed distance Xw1 is stored in the RAM 62, and the process proceeds to step S516.

Specifically, the grindstone diameter measuring unit 56 first acquires the motor rotation angle position θmx at the end of turwing from the X-axis encoder 28E. Then, the acquired motor rotation angle position θmx is converted into an X-axis coordinate value to obtain a third grindstone X coordinate value Xg2. Then, the third grindstone X coordinate value Xg2 is stored in the RAM 62. Next, the X-axis drive motor 28M is driven and controlled to move the groove grinding wheel 21a in the negative direction of the X-axis. Then, the groove grinding wheel 21a is stopped at the position where the proximity sensor 44 first detects the approach of the groove grinding wheel 21a (the position of the proximity detection boundary DP), and the motor rotation angle position θmx is acquired from the X-axis encoder 28E. Then, the acquired motor rotation angle position θmx is converted into an X-axis coordinate value to obtain a fourth grindstone X coordinate value Xg3.

Subsequently, the grindstone diameter measuring unit 56 calculates the second grindstone feed distance Xw1 by subtracting the fourth grindstone X coordinate value Xg3 from the third grindstone X coordinate value Xg2 stored in the RAM 62.
In step S516, the grindstone diameter measuring unit 56 calculates the reference grindstone diameter Dw0, and stores the calculated reference grindstone diameter Dw0 in the RAM 62. After that, the notification of the completion of the grindstone diameter calculation is output to the groove grinding processing unit 51 to end the series of processing and return to the original processing.

Specifically, the grindstone diameter measuring unit 56 has a preset predetermined distance α and a depth of cut A0, a first grindstone diameter Dwn stored in the RAM 62, a first grindstone feed distance Xw0, and a second grindstone feed distance. From Xw1, the reference grindstone diameter Dw0 is calculated according to the above equation (8).
(Thermal deformation correction processing)
Next, the processing procedure of the thermal deformation correction processing executed in the above step S412 will be described with reference to FIG.

When the thermal deformation correction process is executed in step S412, the process first proceeds to step S600, as shown in FIG.
In step S600, the groove grinding unit 51 measures the coordinates (Xow, Zow) of the center point GSc of the groove grinding wheel 21a at the completion of the groove processing before the execution of the third and subsequent grooving processes. Then, the measured center coordinates (Xow, Zow) are stored in the RAM 62. After that, the measurement reference coordinate measurement command is output to the measurement reference coordinate measurement unit 53, and the process proceeds to step S602.

In step S602, the measurement reference coordinate measurement unit 53 measures the measurement reference position coordinates (Xr, Zr) using the touch probe 22 in response to the input of the measurement reference coordinate measurement command. After that, the measured measurement reference position coordinates (Xr, Zr) are stored in the RAM 62, the truing execution command is output to the truing processing unit 54, and the process proceeds to step S604.
In step S604, the truing processing unit 54 executes the truing of the groove grinding grindstone 21a in response to the input of the truing execution command. After that, the grindstone feed distance measurement command is output to the grindstone diameter measuring unit 56, and the process proceeds to step S606.

Specifically, the truing processing unit 54 drives and controls the X-axis drive motor 28M to cut the groove grinding grindstone 21a with respect to the truing point Pt of the diamond dresser 41 by the depth of cut A1 to perform truing.
In step S606, the grindstone diameter measuring unit 56 measures the third grindstone feed distance Xw2 using the proximity sensor 44 in response to the input of the grindstone feed distance measurement command. After that, the measured third grindstone feed distance Xw2 is stored in the RAM 62, and the process proceeds to step S608.

Here, the grindstone diameter measuring unit 56 measures the third grindstone feed distance Xw2, which is the grindstone feed distance from the position at the end of the third and subsequent truing to the proximity detection boundary DP, in the same manner as in step S514.
In step S608, the grindstone diameter measuring unit 56 calculates the distance difference ΔXw, which is the difference (Xw2-Xw1) between the second grindstone feed distance Xw1 and the third grindstone feed distance Xw2 stored in the RAM 62. Then, the calculated distance difference ΔXw is stored in the RAM 62, and the process proceeds to step S610.

In step S610, the grindstone diameter measuring unit 56 outputs a wear measurement command to the measuring instrument 45 of the second truing device 4B to measure the current wear position T1 of the truing point Pt. Then, the measured wear position T1 is stored in the RAM 62, and the process proceeds to step S612.
Specifically, the measuring instrument 45 measures the X coordinate Xt1 and the Z coordinate Zt1 of the current truing point Pt, and stores the measured X coordinate Xt1 as the current wear position T1 in the RAM 62. In addition, the coordinates (Xt1, Zt1) of the current truing point Pt are stored in the RAM 62.

In step S612, the grindstone diameter measuring unit 56 calculates the wear difference ΔT (= T1-T0), which is the difference between the reference wear position T0 and the wear position T1 stored in the RAM 62. Then, the calculated wear difference ΔT is stored in the RAM 62, and the process proceeds to step S614.
In step S614, the grindstone diameter measuring unit 56 calculates the second grindstone diameter Dw from the reference grindstone diameter Dw0, the distance difference ΔXw, and the wear difference ΔT stored in the RAM 62 according to the above equation (9). Then, the calculated second grindstone diameter Dw is stored in the RAM 62. After that, the base position determination command is output to the base position determination unit 55, and the process proceeds to step S616.

In step S616, at the base position determination unit 55, at the position of the base portion 20 when the groove grinding wheel 21a and the third groove bottom portion Db3 of the inner ring work Wi come into contact with each other in response to the input of the base position determination command. Calculate certain base coordinates (Xb, Zb). Then, the calculated base coordinates (Xb, Zb) are stored in the RAM 62, the series of processing is completed, and the original processing is restored.

Specifically, the base position determining unit 55 first has a first relative distance (Xrt = Xr−) from the measurement reference position coordinates (Xr, Zr) and the coordinates (Xt1, Zt1) of the truing point Pt stored in the RAM 62. Xt1, Zrt = Zr-Zt1) is calculated. Next, from the calculated first relative distance (Xrt, Zrt), the reference grindstone diameter Dw0 stored in the RAM 62, the distance difference ΔXw, and the wear difference ΔT, the base coordinates are obtained according to the above equations (10) and (11). (Xb, Zb) is calculated. The base coordinates (Xb, Zb) are coordinates in which the error due to thermal deformation is corrected.

(motion)
Next, an operation example of the second grinding device 1B of the second embodiment will be described with reference to FIGS. 13 to 18 and with reference to FIGS. 19 to 21.
In the second embodiment, the contact point of the grindstone 21a for groove grinding with the processing point Pg and the contact point with the truing point Pt are on opposite sides of the grindstone spindle 21b. In addition, here, the work W to be processed is the master work Wim for the inner ring and the work Wi for the inner ring, and a groove is machined on the outer peripheral surface of the work. These are the differences between the configuration of the outer ring master work Wom and the outer ring work Wo of the first embodiment at the time of processing, and the operations up to the execution timing of the second truing are basically the same. Therefore, the operation after the execution timing of the second truing will be described below.

When the second control device 5B determines that the execution timing of the second truing has come, first, as shown in FIG. 19A, the coordinates of the center point GSc of the grindstone 21a for grooving at the completion of grooving (a). Xow, Zow) is measured. Then, the measured coordinates (Xow, Zow) are stored in the RAM 62.
Subsequently, the second control device 5B measures the work information on the inner ring work Wi after grooving by using the touch probe 22.

Specifically, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled to move the touch probe 22, and as shown in FIG. 19B, the shape of the third groove D3 and the shape of the third groove D3 and the third groove portion D3. The shape of the groove D4 of 4 is measured. That is, the second control device 5B performs a process of bringing the first tip sphere 22d of the touch probe 22 into contact with the surface of the third groove D3 to acquire the coordinate information of the groove surface along the third groove D3. Repeat while changing the Z-axis coordinate position. Similarly, the process of bringing the second tip sphere 22f of the touch probe 22 into contact with the surface of the fourth groove D4 to acquire the coordinate information of the groove surface while changing the Z-axis coordinate position along the fourth groove D4. Repeat.

The second control device 5B has the third groove bottom coordinates (X3, X3) of the third groove bottom portion Db3 based on the measured shape information of the third groove portion D3 and the measured shape information of the fourth groove portion D4. Z3) and the fourth groove bottom coordinates (X4, Z4) of the fourth groove bottom portion Db4 are specified.
Subsequently, the second groove bottom diameter Do (= X3-X4) is calculated based on the third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4). Further, based on the second groove bottom diameter Do and the third and fourth groove bottom coordinates (X3, Z3) and (X4, Z4), "Xoc = X3-Do / 2", "Zoc = Z3 =" The second center coordinates (Xoc, Zoc) are calculated from "Z4". The second control device 5B stores the calculated second groove bottom diameter Do and the second center coordinates (Xoc, Zoc) in the RAM 62.

Subsequently, the second control device 5B uses the above equation (Xow, Zoc) from the coordinates (Xow, Zow) of the center point GSc stored in the RAM 62, the second groove bottom diameter Do, and the second center coordinates (Xoc, Zoc). According to 7), the first grindstone diameter Dwn at the completion of machining is calculated. Then, the calculated first grindstone diameter Dwn is stored in the RAM 62.
Subsequently, the second control device 5B measures the measurement reference position coordinates (Xr, Zr) using the touch probe 22, for example, as shown in FIG. 19 (c). Then, the measured measurement reference position coordinates (Xr, Zr) are stored in the RAM 62.

Subsequently, the second control device 5B measures the reference wear position T0 using the measuring device 45 of the second trueing device 4B, for example, as shown in FIG. 19 (d). Then, the measured reference wear position T0 is stored in the RAM 62.
Next, the second control device 5B measures the first grindstone feed distance Xw0 of the grindstone 21a for groove grinding by using the proximity sensor 44 of the second truing device 4B. Specifically, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled, and as shown in (1) of FIG. Move only to a distant position. Further, the groove grinding grindstone 21a is moved from this position toward the proximity detection boundary DP, and the first grindstone feed distance Xw0 is measured. Then, the measured first grindstone feed distance Xw0 is stored in the RAM 62.

Subsequently, the second control device 5B uses the second truing device 4B to truing the grindstone 21a for groove grinding. Specifically, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled so that, for example, as shown in (2) of FIG. Cut with the depth of cut A0 and perform grooving.
When the second control device 5B finishes the truing, for example, as shown in (3) of FIG. 20A, the second control device 5B moves the groove grinding wheel 21a from the position at the end toward the proximity detection boundary DP. The second grindstone feed distance Xw1 is measured. Then, the measured second grindstone feed distance Xw1 is stored in the RAM 62.

Subsequently, the second control device 5B is referred to from the first grindstone diameter Dwn, the predetermined distance α, the depth of cut A0, the first grindstone feed distance Xw0 and the second grindstone feed distance Xw1 according to the above equation (8). The grindstone diameter Dw0 is calculated. Then, the calculated reference grindstone diameter Dw0 is stored in the RAM 62.
Subsequently, the second control device 5B performs the groove grinding process using the groove grinding wheel 21a after the second truing.

After that, when the second control device 5B determines that the execution timing of the third truing has come, as shown in FIG. 21A, the coordinates of the center point GSc of the grindstone 21a for grooving at the completion of grooving (a). Xow, Zow) is measured. Then, the measured coordinates (Xow, Zow) are stored in the RAM 62.
Subsequently, the second control device 5B measures the measurement reference position coordinates (Xr, Zr) using the touch probe 22, for example, as shown in FIG. 21 (b). Then, the measured measurement reference position coordinates (Xr, Zr) are stored (overwritten) in the RAM 62.

Next, the second control device 5B uses the second truing device 4B to truing the groove grinding grindstone 21a. Specifically, the X-axis drive motor 28M and the Z-axis drive motor 25M are driven and controlled, and as shown in (1) and 21 (c) of FIG. 20 (b), for example, the grindstone for groove grinding 21a Is cut at the cutting amount A1 with respect to the truing point Pt, and truing is performed.

When the second control device 5B finishes the grooving, for example, as shown in (2) and 21 (c) of FIG. 20 (b), the second control device 5B grinds the groove from the position at the end of the growing toward the proximity detection boundary DP. The grindstone 21a is moved, and the third grindstone feed distance Xw2 is measured. Then, the measured third grindstone feed distance Xw2 is stored in the RAM 62.
Subsequently, the second control device 5B calculates the distance difference ΔXw, which is the difference between the second grindstone feed distance Xw1 and the third grindstone feed distance Xw2 stored in the RAM 62. Then, the calculated distance difference ΔXw is stored in the RAM 62.

Subsequently, the second control device 5B measures the current wear position T1 by using the measuring device 45 of the second trueing device 4B, for example, as shown in FIG. 21 (d). Then, the measured wear position T1 and the coordinates (Xt1, Zt1) of the current truing point Pt measured at the time of measurement of T1 are stored in the RAM 62. Subsequently, as shown in FIG. 21D, the wear difference ΔT, which is the difference between the reference wear position T0 stored in the RAM 62 and the current wear position T1, is calculated. Then, the calculated wear difference ΔT is stored in the RAM 62.

Subsequently, the second control device 5B corrects the error due to thermal deformation from the reference grindstone diameter Dw0, the distance difference ΔXw, and the wear difference ΔT stored in the RAM 62 according to the above equation (9). Is calculated. Then, the calculated second grindstone diameter Dw is stored in the RAM 62.
Subsequently, the second control device 5B calculates the first relative distance (Xrt, Zrt) from the measurement reference position coordinates (Xr, Zr) and the coordinates (Xt1, Zt1) of the truing point Pt stored in the RAM 62. .. Then, from the calculated first relative distance (Xrt, Zrt), the second groove bottom diameter Do stored in the RAM 62, the second center coordinates (Xoc, Zoc), and the second grindstone diameter Dw, the above equation is used. According to (10) and (11), the base coordinates (Xb, Zb) when the groove grinding wheel 21a and the third groove bottom Db3 come into contact with each other are calculated.

Specifically, the second control device 5B sets the X-axis coordinate Xb of the position corresponding to the X-axis coordinate Xr of the measurement point Pm at the end of the truing of the base portion 20 to "Xb = Xoc + Do /" according to the above equation (10). It is calculated as "2 + Xrt + Dw". Further, according to the above equation (11), the Z-axis coordinate Zb at the position corresponding to the Z-axis coordinate Zr of the measurement point Pm at the end of the truing of the base portion 20 is calculated as “Zb = Zoc + Zrt”.

That is, as shown in FIG. 22, the base coordinates (Xb, Zb) correspond to the position of the measurement point Pm of the measurement reference 42 when the grindstone 21a for groove grinding at the end of growing is in contact with the growing point Pt. It becomes the coordinates of the position.
In this way, the position of the base portion 20 when the grindstone 21a for groove grinding comes into contact with the third groove bottom portion Db3 is accurately measured with the second grindstone diameter Dw and the truing point Pt having a relatively small thermal effect. And the first relative distance (Xrt, Zrt) from the measurement point Pm. As a result, the relative position change due to the thermal effect can be changed as compared with the case where the second relative distance (Xwt, Zwt), which is the relative distance between the grindstone spindle 21b and the probe shaft 22s, which have a relatively large thermal effect, is used. It becomes possible to suppress.

The second control device 5B starts from the base coordinates (Xb, Zb) in the finishing process after determining the base coordinates, for example, when the target groove bottom diameter Dof is set with respect to the current second groove bottom diameter Do. , (Dof-Di) / 2 are relatively moved to process the inner ring work Wi, so that the work Wi can be finished to a desired size.
After that, until it is time to execute the next truing, the grindstone for groove grinding is used for each inner ring work Wi using the second grindstone diameter Dw calculated this time and the first relative distance (Xrt, Zrt). The base coordinates (Xb, Zb) when the 21a comes into contact with the third groove bottom portion Db3 are determined, and the same finishing processing as described above is performed.

After that, every time it is time to execute the truing, the above series of processes are executed to obtain the measurement reference position coordinates (Xr, Zr), the coordinates of the truing point Pt after the truing (Xt, Zt), and the distance difference ΔXw. And the wear difference ΔT is measured. Further, the second grindstone diameter Dw is calculated from the distance difference ΔXw and the wear difference ΔT, and the first relative distance (Xrt) is calculated from the measurement reference position coordinates (Xr, Zr) and the coordinates (Xt, Zt) of the truing point Pt. , Zrt) is calculated. Then, the base coordinates (Xb, Zb) are based on the second grindstone diameter Dw, the first relative distance (Xrt, Zrt), the second groove bottom diameter Do, and the second center coordinates (Xoc, Zoc). Is determined, and the same finishing process as described above is performed.

On the other hand, when the base position determination process using the second grindstone diameter Dw corrected for the influence of heat and the first relative distance (Xrt, Zrt) is not performed, the grindstone 21a for groove grinding is the third. An example of a method of obtaining the base coordinates (Xb, Zb) when contacting the groove bottom portion Db3 will be described.
First, the shape of the third groove D3 and the shape of the fourth groove D4 of the inner ring work Wi are measured by using the touch probe 22. Further, the second groove bottom diameter Do and the second center coordinates (Xoc, Zoc) are calculated based on the measured shape information.

Next, with the center position of the tip portion of the probe shaft 22s as the position of the base portion 20, the positions of the second center coordinates (Xoc, Zoc) and the center coordinates of the XZ axis of the third tip sphere 22h are aligned. The coordinates at this time are set to the base coordinates (Xb, Zb) = (Xoc, Zoc).
Further, where the grindstone diameter of the grindstone 21a for groove grinding is Dg, the position of the base portion 20 when the grindstone 21a for groove grinding comes into contact with the third groove bottom portion Db3 (that is, the center position of the XZ axis of the third tip ball 22h). ) Can be obtained from the following equations (12) and (13) using the relative distances (Xwt, Zwt) between the grindstone spindle 21b and the probe shaft 22s.

Xb = Xoc + Do / 2 + Dg / 2 + Xwt ・ ・ ・ (12)
Zb = Zoc + Zwt ・ ・ ・ (13)
Here, the second center coordinates (Xoc, Zoc), which are measured values, and the second groove bottom diameter Do are values that are not affected by thermal deformation. On the other hand, the grindstone spindle 21b and the probe shaft 22s have a long distance between them via the structure as in the first embodiment, and in particular, in a large grinding machine (large grinding machine) or the like, the distance is several [m]. Become. In addition, as in the first embodiment, there is a heat generating source in the structure due to the grindstone spindle motor 21d.

Further, as in the first embodiment, the grindstone 21a for grooving during grooving and the diamond dresser 41 of the second grooving device 4B have a long distance between them via the structure, and in particular, a large grinding machine. In such cases, it can be several [m]. In addition, under the influence of heat, the grindstone diameter Dg changes by twice the relative positional relationship between the grindstone 21a for groove grinding and the diamond dresser 41. Further, there are a heat source caused by grooving at the machining point Pg and a heat source caused by the work rotation motor 35.

From the above, the second relative distances (Xwt, Zwt) and the grindstone diameter Dg are distances and dimensions that are easily affected by heat, and errors are likely to occur due to thermal deformation of the structure.
On the other hand, the measurement reference 42 and the diamond dresser 41 of the second truing device 4B are in a thermally stable position because the distance between them via the structure is short and there are few heat sources in the periphery. It becomes a component. That is, the first relative distance (Xrt, Zrt) between the measurement point Pm of the measurement reference 42 and the truing point Pt of the diamond dresser 41 is unlikely to cause an error due to thermal deformation of the structure. In addition, the proximity sensor 44 supported by the sensor support 43 made of a low-line expansion alloy with small thermal deformation measures the accurate second grindstone diameter Dw. That is, the second grindstone diameter Dw is a value in which the influence of heat is taken into consideration.

Here, the grindstone 21a for groove grinding corresponds to a rotary grindstone, the grindstone spindle 21b corresponds to a rotary shaft, the grindstone spindle motor 21d corresponds to a rotary drive source, and the first truing device 4A corresponds to a truing portion. , Diamond dresser 41 corresponds to the dresser.
Further, the sensor support unit 43 corresponds to the sensor support member, the groove grinding unit 51 corresponds to the grinding unit, the work information measuring unit 52 corresponds to the work shape measuring unit, and the measuring instrument 45 corresponds to the trueing point coordinates. Corresponds to the measuring unit.

(Action and effect of the second embodiment)
The second grinding device 1B according to the second embodiment is configured such that the position of the machining point Pg is located on the opposite side of the grinding wheel spindle 21b from the truing point Pt when viewed from the Y-axis direction. .. In addition, a groove grinding unit 21 having a grindstone spindle 21b, a grindstone for groove grinding 21a attached to the tip of the grindstone spindle 21b, and a grindstone spindle motor 21d for rotationally driving the grindstone spindle 21b is provided. Further, a work support member 32 that fixedly supports the work W, a table 31 that rotatably supports the work support member 32 in an axial direction parallel to the grindstone spindle 21b via the work rotation spindle 33, and a work rotation. A work support portion 3 having a work rotation motor 35 for rotationally driving the work spindle 33 is provided. Further, a touch probe 22 having a probe shaft 22s and a stylus 22t provided at the tip of the probe shaft 22s is provided. Further, it includes a base portion 20 that fixedly supports the groove grinding portion 21 and the touch probe 22 in parallel with the axis, and a measurement reference 42 that is a position reference of the touch probe 22. Further, the dresser base 40 is provided with a first truing device 4A having a dresser base 40 and a diamond dresser 41 for truing the groove grinding grindstone 21a provided on the side of the dresser base 40 facing the work support portion 3. Further, a moving mechanism that moves the first and second base portions 23 and 26 to the grinding position of the work W, the truing position of the grindstone 21a for groove grinding, the measurement position of the shape of the work W, and the measurement position of the measurement reference 42. It has a part. This movement mechanism unit serves as a mechanism unit for moving the first base unit 23 of the base unit 20 in the Z-axis direction, such as a Z-axis drive motor 25M, a first left linear motion guide device 24L, and a first right. A linear motion guide device 24R and a first ball screw device 25 are provided. Further, this moving mechanism unit is a mechanism unit for moving the second base unit 26 of the base unit 20 in the X-axis direction, such as an X-axis drive motor 28M, a second left linear motion guide device 27L, and a second. The right linear motion guide device 27R and the second ball screw device 28 are provided.

Then, in the second grinding device 1B according to the second embodiment, the groove grinding unit 51 drives the grindstone spindle motor 21d, the workpiece rotation motor 35, the X-axis drive motor 28M, and the Z-axis drive motor 25M. A process of grinding a work W by controlling and bringing a groove grinding grindstone 21a, which rotates at a preset rotation speed for groove grinding, into contact with a work W fixedly supported by a work support member 32 of a work support portion 3. I do. The work information measuring unit 52 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M, and grinds the stylus 22t of the touch probe 22 fixedly supported by the work support member 32 of the work support unit 3. The work W is brought into contact with the processed work W to measure the shape of the work W. The measurement reference coordinate measurement unit 53 drives and controls the X-axis drive motor 28M and the Z-axis drive motor 25M to bring the stylus 22t of the touch probe 22 into contact with the measurement reference 42, and the measurement point Pm of the measurement reference 42. Performs a process of measuring the position coordinates (Xr, Zr) of. The grooving processing unit 54 drives and controls the grindstone spindle motor 21d, the X-axis drive motor 28M, and the Z-axis drive motor 25M to drive and control the groove grinding grindstone 21a that rotates at a preset rotation speed for grooving. The groove grinding grindstone 21a is trued by contacting the truing point Pt of the diamond dresser 41 of the truing device 4A. The measuring instrument 45 of the first truing device 4A measures the position coordinates (Xt, Zt) of the truing point Pt. A proximity sensor 44 is provided at a position facing the truing point Pt and away from the truing point Pt in the X-axis direction from the length of the grindstone diameter of the grindstone 21a for groove grinding. The grindstone diameter measuring unit 56 measures the second grindstone diameter Dw, which is the diameter of the grindstone 21a for groove grinding, using the proximity sensor 44.

Here, the measurement reference 42 and the diamond dresser 41 are the first relative distances between the position coordinates (Xr, Zr) of the measurement point Pm due to the thermal influence and the position coordinates (Xt, Zt) of the truing point Pt. The coordinates are arranged so that the error from the distance (Xrt, Zrt) is within the range satisfying the preset target machining accuracy. Specifically, in the second embodiment, the second truing device 4B is arranged at a position as far as possible from the heat source, and the measurement reference 42 is placed on the upper part of the dresser base 40 of the second truing device 4B. It is provided. More specifically, in the measurement reference 42, for example, when the frame of the dresser base 40 is made of iron and the target processing accuracy is set to 5 [μm] or less, the distance from the diamond dresser 41 via the structure is 41 [cm]. ] It is provided at the following positions.

Further, the proximity sensor 44 is supported by the dresser base 40 constituting the second truing device 4B via the sensor support portion 43, and the sensor support portion 43 is made of a member made of a low-line expansion alloy. ..
Further, the base position determination unit 55 determines the first relative distance (Xt, Zt) between the position coordinates (Xr, Zr) of the measurement point Pm of the measurement reference 42 and the position coordinates (Xt, Zt) of the grinding point Pt at the end of the grinding wheel. Based on Xrt, Zrt), the second grindstone diameter Dw measured by the grindstone diameter measuring unit 56 at the end of truing, and the shape information of the work W, when the grindstone 21a for groove grinding comes into contact with the work W during grinding. The position coordinates (Xb, Zb) of the base portion 20 corresponding to the representative position coordinates are determined.

Further, the work W is an annular member (work W for outer ring, work Wi for inner ring) that constitutes a raceway ring of a rolling bearing. Then, the groove grinding process section 51 of the second embodiment performs a groove grinding process for grinding a groove serving as a rolling path of the rolling element on the outer peripheral surface of the inner ring work Wi. The work information measuring unit 52 measures the shapes of the third and fourth groove portions D3 and D4 facing the back through the center of the inner ring work Wi of the groove formed on the outer peripheral surface of the inner ring work Wi. In addition, these grooves are based on the coordinates (X3, Z3) of the third groove bottom Db3 and the coordinates (X4, Z4) of the fourth groove bottom Db4 specified from the shapes of the third and fourth groove D3 and D4. The process of calculating the second groove bottom diameter Do, which is the linear distance between the bottoms, and the second center coordinates (Xoc, Zoc) of the inner ring work Wi is performed. The base position determination unit 55 determines the first relative distance (Xrt, Zrt) between the position coordinates (Xr, Zr) of the measurement reference 42 and the position coordinates (Xt, Zt) of the truing point Pt at the end of truing, and the end of truing. Based on the second grindstone diameter Dw at the time, the second groove bottom diameter Do, and the second center coordinates (Xoc, Zoc), the groove grinding grindstone 21a is used as the third outer ring work Wo during groove grinding. The position coordinates (Xb, Zb) of the base portion 20 corresponding to the position coordinates of the representative when in contact with the groove bottom portion Db3 are determined.

Specifically, the grindstone diameter measuring unit 56 determines the coordinates (Xow, Zow) of the center point of the grindstone 21a for groove grinding when the machining of the inner ring work Wi is completed, the second groove bottom diameter Do, and the grindstone diameter measuring unit 56 at the execution timing of the true ring. From the second center coordinates (Xoc, Zoc), a process of calculating the first grindstone diameter Dwn at the completion of machining (first grindstone diameter calculation process) is performed according to the above equation (7). The first when the grindstone diameter measuring unit 56 moves the grindstone 21a for groove grinding from a position separated by a predetermined distance α from the truing point Pt to the proximity detection boundary DP of the proximity sensor 44 after calculating the first grindstone diameter Dwn. The grindstone feed distance Xw0 is measured. The grindstone diameter measuring unit 56 moves the grindstone 21a for groove grinding from the position at the end after cutting the grindstone 21a for groove grinding by the depth of cut A0 after measuring the first grindstone feed distance Xw0 to the proximity detection boundary DP. The second grindstone feed distance Xw1 is measured. The grindstone diameter measuring unit 56 determines the reference grindstone diameter of the grindstone 21a for groove grinding according to the above formula (8) from the first grindstone diameter Dwn, the first grindstone feed distance Xw0, the depth of cut A0 and the second grindstone feed distance Xw1. A process of calculating Dw0 (second grindstone diameter calculation process) is performed. The grindstone diameter measuring unit 56 moves the grindstone 21a for groove grinding to the proximity detection boundary DP from the position at the end after cutting the grindstone 21a for groove grinding with the depth of cut A1 and grooving at the subsequent execution timing of truing. The third grindstone feed distance Xw2 at the time is measured. The grindstone diameter measuring unit 56 calculates the distance difference ΔXw, which is the difference between the second grindstone feed distance Xw1 and the third grindstone feed distance Xw2. When the grindstone diameter measuring unit 56 measures the reference grindstone diameter Dw0, the reference wear position T0 in the X-axis direction of the truing point Pt, and the third grindstone feed distance Xw2, the wear position T1 of the truing point Pt in the X-axis direction. The wear difference ΔT, which is the difference from the above, is calculated. The grindstone diameter measuring unit 56 calculates the second grindstone diameter Dw at the end of growing from the reference grindstone diameter Dw0, the distance difference ΔXw, and the wear difference ΔT according to the above equation (9) (third grindstone). Diameter calculation processing) is performed.

Then, the base position determining unit 55 determines the first relative distance (Xrt, Zrt) between the measurement reference position coordinates (Xr, Zr) and the coordinates (Xt, Zt) of the truing point Pt at the end of truing, and at the end of truing. From the second grindstone diameter Dw, the second groove bottom diameter Do, and the second center coordinates (Xoc, Zoc), the base corresponding to the representative position coordinates according to the above equations (10) and (11). The coordinates (Xb, Zb) of the part 20 are calculated.

With the above configuration, when determining the position coordinates (Xb, Zb) of the base portion 20, the second grindstone diameter Dw, which is not affected by heat, and is less susceptible to heat, as compared with the conventional positioning method. Since the first relative distance (Xrt, Zrt) is used, relatively stable machining becomes possible. Further, it is possible to suppress the influence of thermal deformation only by changing the positional relationship between the truing point Pt and the measurement reference 42 regardless of the distance via the structure, that is, the size of the grinding device. This effect is due to the large difference between the first relative distance Xrt and the second relative distance Xwt in the X-axis direction and the difference between the first relative distance Zrt and the second relative distance Zwt in the Z-axis direction. It becomes remarkable in the grinding machine. Further, since the sensor support portion 43 that supports the proximity sensor 44 may have a simple shape and may be smaller than the dimensions of the grinding apparatus, it is compared with the case where a low-line expansion alloy is used for a large structural member. It can be introduced at low cost. Further, since it is not necessary to perform complicated thermal deformation control, it is not necessary to upgrade the equipment, and the cost for that is not required. That is, it is possible to perform positioning in which the influence of thermal deformation is corrected, which is simpler and lower cost than the conventional one.

(Modification example)
(1) In the first embodiment, the outer ring work Wo has been described as an example, but the present invention is not limited to this configuration, and as shown in FIG. 23 (a), the inner ring work Wi is also described in the first embodiment. The invention according to the above is applicable. In this case, the second groove bottom diameter Do and the second center coordinates (Xoc, Zoc) of the inner ring work Wi are measured by the same procedure as in the second embodiment. Further, in the calculation of the base coordinates (Xb, Zb), the following equations (14) and (15) are used instead of the above equations (3) and (4).

Xb = Xoc-Do / 2 + Xrt ... (14)
Zb = Zoc + Zrt ... (15)
(2) In the second embodiment, the inner ring work Wi has been described as an example, but the present invention is not limited to this configuration, and as shown in FIG. 23 (b), the outer ring work Wo is also included in the second embodiment. The invention according to the above is applicable. In this case, the first groove bottom diameter Di and the first center coordinates (Xci, Zci) of the outer ring work Wo are measured by the same procedure as in the first embodiment. Further, in the calculation of the base coordinates (Xb, Zb), the following equations (16) and (17) are used instead of the above equations (10) and (11).

Xb = Xci-Di / 2 + Dw + Xrt ... (16)
Zb = Zci + Zrt ・ ・ ・ (17)
(3) In the second embodiment, the proximity sensor 44 is used to measure each grindstone feed distance, but the configuration is not limited to this. For example, by using the laser distance sensor, it is possible to measure the first to third grindstone feed distances Xw0 to Xw2 without the operation of feeding the grindstone 21a for groove grinding in the negative direction of the X axis. This makes it possible to shorten the cycle time. Further, another measuring instrument may be used as long as the accurate second grindstone diameter Dw of the grindstone 21a for groove grinding after truing can be measured.

(4) In each of the above embodiments, the diamond dresser 41 is composed of a point dresser having a tip portion Pt formed by polishing diamond into a conical shape, but the present invention is not limited to this configuration. For example, another configuration such as a configuration including a tip portion Pt polished into a pyramid shape may be used.
(5) In each of the above embodiments, the stylus 22t of the touch probe 22 has four tip spheres arranged in a cross shape, and the surface position of the groove portion does not change the rotational position of the touch probe 22 in the direction around the probe shaft 22s. However, the configuration is not limited to this configuration. For example, when the tip sphere and the arm portion of the stylus 22t are reduced to two facing each other on the back surface, the position of the stylus 22t is rotated around the probe shaft 22s by a rotation drive mechanism or the like, so that each facing groove portion is formed. It may be configured to correspond. Further, the tip ball of the stylus 22t and the arm may be combined into one, and the stylus may be rotated for each groove portion to correspond to each other. Further, a tip sphere as a stylus may be provided only at the tip of the probe shaft 22s. In this case, the probe shaft 22s may be configured to rotate in the X-axis direction around the fulcrum with the base end portion of the probe shaft 22s as the fulcrum.

(6) In each of the above embodiments, the measurement reference 42 is provided on the upper part of the dresser base 40 of the trueing device, but the present invention is not limited to this configuration and may be provided at another position such as a side portion. Further, the configuration is not limited to the provision in the truing device, and if the distance between the two is within the close distance range and the thermal influence is within the permissible range, the configuration is provided at another position in the grinding device. May be.

(7) In each of the above embodiments, in the position measurement process of the grinding measurement unit 2, various coordinate positions are measured by a combination of a motor, a ball screw, and an encoder, but the configuration is not limited to this. For example, various coordinate positions may be measured using a measuring instrument such as a linear scale or a laser displacement meter.

1A, 1B ... 1st and 2nd grinding devices, 2 ... Grinding measuring section, 3 ... Work support section, 4A, 4B ... 1st and 2nd truing devices, 5A, 5B ... 1st and 2nd control devices , 20 ... Base part, 21 ... Groove grinding part, 21a ... Groove grinding wheel, 21b ... Grinding spindle, 21c ... Grinding spindle housing, 21d ... Grinding spindle motor, 22 ... Touch probe, 22a ... Probe housing, 22b ... Probe Head, 22s ... probe shaft, 22t ... stylus, 23 ... first base, 24L ... first left linear motion guide device 24L, 24R ... first right linear motion guide device, 25 ... first ball screw Device, 25M ... Z-axis drive motor, 26 ... 2nd base, 27L ... 2nd left linear motion guidance device, 27R ... 2nd right linear motion guidance device, 28 ... 2nd ball screw device, 28M ... X-axis drive motor, 51 ... Groove grinding unit, 52 ... Work information measurement unit, 53 ... Measurement reference coordinate measurement unit, 54 ... Truing processing unit, 55 ... Base position determination unit, 56 ... Grinding stone diameter measurement unit, 41 ... Diamond dresser, 42 ... Measurement standard, 43 ... Sensor support, 44 ... Proximity sensor, 45 ... Measuring instrument

Claims (10)

Support stand and
A first rotary drive that is spaced above the support and drives the first rotary shaft, the rotary grindstone attached to the tip of the first rotary shaft, and the first rotary shaft. It has a grinding part including a source, and has a touch probe including a sensor shaft and a contact type stylus provided at the tip of the sensor shaft, and has a vertical axis of the grinding part and the touch probe. With a base that is fixedly supported in parallel with
Rotatably rotate the second to support the workpiece support member for fixing and supporting the placed in the work on the support base at a second through said rotation axis the first rotation axis parallel to axis A work support having a second rotational drive source that rotationally drives the shaft, and
It has a moving drive source and a guide member for moving the base portion, and by the driving force of the moving drive source, the grinding position of the work, the truing position of the rotary grindstone, the measurement position of the shape of the work, and the touch. A moving mechanism unit that moves the base unit in the orthogonal biaxial direction along the guide member to the measurement position of the measurement reference that serves as the position reference of the probe.
Wherein a on the support base, the dresser base with the workpiece support and truing portion dresser for truing said grinding wheel is provided on the opposite side,
By driving and controlling the first and second rotary drive sources and the mobile drive source, the rotary grindstone that rotates at a rotational speed for grinding is brought into contact with the work fixedly supported by the work support member. A grinding unit that grinds the work and
A work shape in which the moving drive source is driven and controlled so that the stylus of the touch probe is brought into contact with the work after grinding, which is fixedly supported by the work support portion, and the shape of the work is measured. Measurement processing unit and
A measurement reference coordinate measuring unit that performs a process of driving and controlling the moving drive source, bringing the touch probe into contact with the measurement reference, and measuring the position coordinates of the measurement reference.
A trueing that drives and controls the first rotary drive source and the mobile drive source to bring the rotary grindstone that rotates at the rotational speed for truing into contact with the dresser of the true truing portion to truing the rotary grindstone. Processing unit and
A truing point coordinate measuring unit that measures the position coordinates of the truing point, which is the contact point of the dresser that comes into contact with the rotating grindstone during truing.
The position coordinates of the base portion at the end of the truing are represented by the position coordinates of the measurement reference, and the relative positions of the position coordinates of the measurement reference and the position coordinates of the truing point measured by the truing point coordinate measurement unit at the end of the truing. Based on the distance and the shape information of the work measured by the work shape measurement processing unit, the position coordinates of the base portion corresponding to the representative position coordinates when the rotary grindstone comes into contact with the work during grinding are obtained. The base position determination unit to determine and
The work is provided with a finishing part for finishing the work based on the position coordinates of the base part determined by the base position determining part .
A grinding device provided on the upper part of the dresser base so that the measurement reference is within a range in which an error due to a thermal effect in grinding satisfies a preset target machining accuracy. When the position of the machining point, which is the contact point between the rotary grindstone and the work during grinding, is viewed from the axial direction orthogonal to the two orthogonal axial directions, the trueing point sandwiches the first rotary axis. The grinding device according to claim 1 , which is configured to be located on the side. The work is an annular member that constitutes a raceway ring of a rolling bearing.
The grinding unit is configured to perform a groove grinding process for grinding a groove serving as a rolling path of a rolling element on the peripheral surface of the work.
The work shape measurement processing unit measures the shapes of two groove portions facing each other or facing each other back and forth through the center of the work of the groove formed on the peripheral surface of the work, and is specified from the shapes of the two groove portions. It is configured to perform a process of calculating the groove bottom diameter, which is the linear distance between the groove bottoms, and the coordinates of the center position of the work, based on the coordinates of the groove bottom.
The base position determining unit is based on the relative distance between the position coordinates of the measurement reference and the position coordinates of the truing point at the end of truing, the groove bottom diameter, and the coordinates of the center position of the work, and is said to be said at the time of grinding. The grinding apparatus according to claim 2 , wherein the position coordinates of the base portion corresponding to the position coordinates of the representative when the rotary grindstone comes into contact with the work are determined. The work is a member that constitutes the outer ring of the rolling bearing.
The two orthogonal axes are composed of a Z axis, which is one axis in the vertical direction, and an X axis, which is the other axis in the direction in which the work support portion and the truing portion are aligned.
The relative distance between the X-axis coordinate and the Z-axis coordinate of the measurement reference and the X-axis coordinate and the Z-axis coordinate of the truing point at the end of the truing is set to Xrt and Zrt, and the groove of the groove formed in the member constituting the outer ring. The bottom diameter of the first groove, which is the bottom diameter, is Di, and the X-axis coordinates of the center positions of the members constituting the outer ring and the first center coordinates, which are the Z-axis coordinates, are Xci and Zci. The grinding apparatus according to claim 3 , wherein the X-axis coordinates and Z-axis coordinates of the corresponding base portion are set to Xb and Zb, and the Xb and Zb are calculated according to the following equations (1) and (2).
Xb = Xci + Xrt + Di / 2 ... (1)
Zb = Zci + Zrt ・ ・ ・ (2) When the position of the machining point, which is the contact point between the rotary grindstone and the work during grinding, is viewed from the axial direction orthogonal to the two orthogonal axial directions, the trueing point sandwiches the first rotary axis. It is configured to be located on the opposite side of the
A grindstone diameter measuring unit for measuring the grindstone diameter, which is the diameter of the rotary grindstone, is provided.
The base position determining unit includes the relative distance between the position coordinates of the measurement reference and the position coordinates of the truing point at the end of the truing, the grindstone diameter measured by the grindstone diameter measuring unit at the end of the truing, and the work. The grinding apparatus according to claim 1 , wherein the position coordinates of the base portion corresponding to the position coordinates of the representative when the rotary grindstone comes into contact with the work during grinding are determined based on the shape information. The work is an annular member that constitutes a raceway ring of a rolling bearing.
The grinding unit is configured to perform a groove grinding process for grinding a groove serving as a rolling path of a rolling element on the peripheral surface of the work.
The work shape measurement processing unit measures the shapes of two groove portions facing each other on the back surface of the groove formed on the peripheral surface of the work through the center of the work, and is specified from the shapes of the two groove portions. It is configured to perform processing to calculate the groove bottom diameter, which is the linear distance between the groove bottoms, and the coordinates of the center position of the work, based on the coordinates of the groove bottom.
The base position determining unit is a relative distance between the position coordinates of the measurement reference at the end of the truing and the position coordinates of the truing point, the diameter of the grindstone at the end of the truing, the groove bottom diameter, and the center position of the work. The grinding apparatus according to claim 5 , wherein the position coordinates of the base portion corresponding to the position coordinates of the representative when the rotary grindstone comes into contact with the work during grinding are determined based on the coordinates of the above. The work is a member that constitutes an inner ring of the rolling bearing.
The two orthogonal axes are composed of a Z axis, which is one axis in the vertical direction, and an X axis, which is the other axis in the direction in which the work support portion and the truing portion are aligned.
The relative distance between the X-axis coordinate and Z-axis coordinate of the measurement reference and the X-axis coordinate and Z-axis coordinate of the truing point at the end of truing is defined as Xrt and Zrt, and the diameter of the grindstone at the end of truing is defined as Dw. The second groove bottom diameter, which is the groove bottom diameter of the groove formed in the member constituting the inner ring, is set to Do, and the X-axis coordinate and the Z-axis coordinate of the center position of the member constituting the inner ring are the second center coordinates. Is Xoc and Zoc, the X-axis coordinates and Z-axis coordinates of the base portion corresponding to the representative position coordinates are Xb and Zb, and the Xb and Zb are calculated according to the following equations (3) and (4). 6. The grinding apparatus according to 6.
Xb = Xoc + Do / 2 + Xrt + Dw ... (3)
Zb = Zoc + Zrt ・ ・ ・ (4) A proximity sensor provided at a position facing the truing point and distant from the truing point in the X-axis direction from the length of the grindstone diameter is provided.
The grindstone diameter measuring unit
At the execution timing of the truing, the X-axis coordinates Xow and the Z-axis coordinates Zow of the center point of the rotary grindstone when the machining of the work is completed, the second groove bottom diameter Do, and the second center coordinates Xoc and Zoc. Therefore, according to the following formula (5), the first grindstone diameter calculation process for calculating the first grindstone diameter Dwen, which is the grindstone diameter at the completion of machining, and
After calculating the first grindstone diameter Dwn, the first grindstone feed when the rotary grindstone is sent from a position separated by a predetermined distance α from the trueing point to the proximity detection boundary which is the boundary of the detection range of the proximity sensor. When the distance Xw0 is measured, and after the first grindstone feed distance Xw0 is measured, the rotary grindstone is cut by the depth of cut A0 and trued, and then the rotary grindstone is fed from the position at the end of the truing to the proximity detection boundary. The second grindstone feed distance Xw1 is measured, and from the first grindstone diameter Dwn, the first grindstone feed distance Xw0, the depth of cut A0, and the second grindstone feed distance Xw1, according to the following equation (6). A reference grindstone diameter calculation process for calculating the reference grindstone diameter Dw0, which is the reference grindstone diameter of the rotary grindstone, and
In the subsequent execution timing of the truing, the third grindstone feed distance Xw2 when the rotary grindstone is sent to the proximity detection boundary is set from the position at the end of the truing after the rotary grindstone is cut with the cutting amount A1 and trued. The distance difference ΔXw, which is the difference between the second grindstone feed distance Xw1 and the third grindstone feed distance Xw2, is calculated, and the wear of the truing point in the X-axis direction when the reference grindstone diameter Dw0 is calculated is calculated. The wear difference ΔT, which is the difference between the position T0 and the wear position T1 of the trueing point in the X-axis direction when measuring the third grindstone feed distance X2, is calculated, and the reference grindstone diameter Dw0, the distance difference ΔXw, and the above. and a wear difference [Delta] T, according to the following equation (7), grinding of claim 7 to perform the second grinding diameter calculation process, the calculating a second grinding wheel diameter Dw is grindstone diameter during the truing ends apparatus.
Dwn = 2 × (Xow-Xoc) -Do ・ ・ ・ (5)
Dw0 = Dwn-2 × (Xw1-Xw0-A0) ... (6)
Dw = Dw0-2 × (ΔXw + ΔT) ・ ・ ・ (7) The proximity sensor is supported by the dresser base constituting the trueing portion via a sensor support member.
The grinding apparatus according to claim 8 , wherein the sensor support member is made of a member made of a low-line expansion alloy. A method for manufacturing a rolling bearing, wherein the work is a raceway ring of a rolling bearing, and the rolling bearing is manufactured by using the grinding device according to any one of claims 1 to 9.

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