JP3819530B2 - Ultra-precision truing equipment for grinding wheels - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultra-precision truing device for grinding wheels.
Ultra-precision machining technology has been developed mainly for the production of optical parts such as lenses and semiconductor parts such as silicon wafers, but in recent years it has expanded to power transmission parts represented by bearings and gears as well as precision machine parts. It's getting on.
[0002]
Gears are used in all industrial machines, and the required accuracy has become stricter in recent years. Further, if the tooth surface roughness is improved, the transmission load tolerance increases by a factor of 3 with Hertz stress. It has been announced that it has been confirmed that the ideal tooth surface roughness to achieve this is about 0.1 μm in Rmax.
[0003]
In the industry, based on the above recognition, there is a move to actively adopt grinding gears with good finishing accuracy, but the shape error and surface roughness of mass-produced base gears are Rmax of about 2.0μm due to ordinary grinding wheels, productivity In the case of a high CBN wheel, the actual condition is that Rmax is about 5.0 μm.
[0004]
Currently, many CBN wheels are used for gear grinding, but the irregular shape accuracy and abrasive height of this wheel naturally affect the machining accuracy and surface roughness of the gear. There is also a demand for improved performance of truing devices that have the same precision and abrasive height. The present invention relates to such a truing device.
[0005]
[Prior art]
Super-abrasive grains such as CBN and diamond are hard and brittle materials. However, micro-cutting of these hard and brittle materials is based on fracture mechanics based on brittle mode (brittle fracture type material removal) and ductile mode (plastic deformation type material removal). It is known that there is.
[0006]
In the brittle mode, as shown in FIG. 10, cracks are generated in the material, and the material is removed by the accumulation of cracks, so that the processing accuracy is deteriorated. On the other hand, in the ductility mode, as shown in FIG. 9, cracks do not occur and continuous chips are produced, so that the machining accuracy is increased. Material removal in the cutting of hard and brittle materials is normally in brittle mode, but it is known that cutting by plastic deformation that goes up to ductility mode can be obtained by controlling high cutting speed and fine cutting (“precision machining”). "The most advanced technology", pages 133-141, first published on March 25, 1996, published by Industrial Research Co., Ltd.).
[0007]
Furthermore, as shown in FIG. 11, it is also known that if the truing device has insufficient rigidity and a movement error occurs in the cutting tool, cracks are scattered and finishing accuracy is lowered.
[0008]
However, there is no conventional truing device capable of micro-cutting (for example, feed accuracy of 0.1 μm or less), and high precision wheels with submicron shape error and surface roughness due to ductility mode cutting due to lack of rigidity or backlash of each part. There was no truing device capable of producing
In addition, there was no device capable of super-precision truing the wheel base metal and abrasive grains on the same machine.
[0009]
[Problems to be solved by the invention]
In view of the above circumstances, the present invention enables truing in a ductile mode by fine cutting of a steel wheel base metal and a brittle CBN abrasive grain, and is electrodeposited on the wheel base metal and the base metal. An object is to provide an ultra-precision truing device capable of truing the produced superabrasive wheel on the same machine.
[0010]
[Means for Solving the Problems]
The truing device according to claim 1, a base, a wheel drive table that reciprocates in the X-axis direction on the base, a dresser drive table that reciprocates in the Z-axis direction orthogonal to the X-axis on the base, A wheel drive comprising a wheel bearing mounted on the wheel drive table, a wheel spindle that is rotatably supported by the wheel bearing and is attached to a truing base or a wheel, and a wheel drive motor that rotates the wheel spindle. , A dresser bearing mounted on the dresser drive table, a dresser spindle that is rotatably supported by the dresser bearing and attaches a dresser that is a truing tool, and a dresser drive motor that rotates the dresser spindle The base is made of low thermal expansion casting. The dresser bearing is a hydrostatic oil bearing, and both the wheel drive table and the dresser drive table have V-V guide surfaces and V-V guide surfaces formed on the lower sliding surfaces thereof. And the upper sliding surface is in contact with a static pressure guide surface formed on the base, for reciprocating the wheel drive table and for reciprocating the dresser drive table. Each nut holder of each nut screwed to each feed screw is guided by a linear ball guide on the base, and is coupled to each of the wheel drive table and the dresser drive table via a static pressure coupling. It is characterized by being.
[0011]
In the invention of claim 1, whether or not to install the base on the damping table is arbitrary, but the truing device of claim 2 is characterized in that the base is installed on the damping table. .
[0012]
The truing device according to claim 3 is the invention according to claim 1 or 2, wherein each drive motor of the wheel drive table and the dresser drive table is a direct drive type servo motor, and the control device of each drive motor has a control resolution. A numerical controller of 0.01 μm or less, wherein the feedback sensors of the two drive tables are linear laser scales with a minimum resolution of 0.01 μm.
[0013]
A truing device according to a fourth aspect is characterized in that, in the invention according to the first, second or third aspect, an AE sensor is installed on the dresser bearing.
[0014]
The truing device according to claim 5 is the invention according to claim 1, 2, 3 or 4, wherein the arbor gripping mechanism for attaching the metal base or wheel to be trued is incorporated in the pull stud fixed to the arbor and the wheel main shaft. However, it is a collet that can be opened and closed from the outside.
[0015]
According to the first aspect of the present invention, low thermal expansion cast iron is used for the base, distortion caused by heat generation during processing is suppressed to prevent a decrease in processing accuracy due to deformation, and ultra-precision grinding is performed against processing reaction force. Adopting VV guide surface and needle roller bearing for guide structure of drive table, enabling high friction table movement with low frictional resistance and horizontal direction, and high pressure in the vertical direction with static pressure guide surface. Stiffness, the static pressure oil bearing is used as the dresser bearing to improve static rigidity and rotational accuracy, and the linear ball guide and static pressure coupling suppress the runout and frictional resistance of the nut of the feed screw. Thus, the rigidity of the truing device can be made sufficiently high so that the movement error of the cutting tool and the scattering of cracks can be prevented.
[0016]
According to invention of Claim 2, propagation of an external vibration can be interrupted | blocked by a damping table, and the fall of the processing precision by an external vibration can be prevented.
[0017]
According to the invention of claim 3, a fine cut of 0.1 μm or less necessary for the ductility mode is achieved by a high-torque high-accuracy direct drive servo actuator, a numerical controller with a control resolution of 0.01 μm and a linear laser scale with a minimum resolution of 0.01 μm This allows for ultra-precision truing.
[0018]
According to invention of Claim 4, the AE wave at the time of crushing of an abrasive grain can be detected reliably, and the air cut at the time of truing, shortening of cycle time, and excessive cutting can be prevented.
[0019]
According to the invention of claim 5, the arbor can be easily exchanged by opening and closing the collet from the outside, and various base metals and wheels can be easily exchanged. Truing of the base metal and the wheel on the same machine Can be made possible.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a truing device according to an embodiment of the present invention, and a schematic configuration will be described based on this drawing.
[0021]
In the figure, reference numeral 1 denotes a vibration control table, and a base 2 is installed on the upper surface thereof. A wheel drive table 3 and a dresser drive table 4 are arranged in an L shape on the base 2, the wheel drive table 3 reciprocates in the X axis direction, and the wheel drive table 4 moves in the Z axis direction orthogonal to the X axis. It is designed to reciprocate. That is, a two-axis grinding machine system is configured. Whether or not to use a damping table is arbitrary, but using it is preferable because it can suppress propagation of external vibration.
The table guide structure of each of the drive tables 3 and 4 is composed of a VV guide surface 40 and the like, details of which will be described later.
[0022]
Mounted on the wheel drive table 3 is a wheel drive unit including a wheel bearing 10, a wheel main shaft 11 rotatably supported by the wheel bearing 10, and a wheel drive motor 12 that rotates the wheel main shaft 11. Yes. The wheel main shaft 11 and the drive motor 12 are connected by a belt transmission mechanism or the like. A gate-shaped sensor support 5 is attached to the end of the base 3, a fixed portion 7 a of the laser linear scale 7 is attached to the sensor support 5, and a movable portion 7 b of the laser linear scale 7 is provided on the table 3. Installed.
[0023]
On the dresser drive table 4, a dresser drive unit comprising a dresser bearing 20, a dresser main shaft 21 rotatably supported by the dresser bearing 20, and a dresser drive motor 22 that rotates the dresser main shaft 21 is mounted. ing. The dresser main shaft 21 and the drive motor 22 are directly connected. A gate-shaped sensor support 6 is attached to the end of the base 4, a fixed portion 8 a of the laser linear scale 8 is attached to the sensor support 6, and a movable portion 8 b of the laser linear scale 8 is placed on the table 4. Is installed.
[0024]
The base 2 and the sensor support portions 5 and 6 are made of low thermal expansion cast iron to prevent distortion caused by heat generation during processing as much as possible.
[0025]
Next, details of the guide structure of the drive tables 3 and 4 will be described. FIG. 2 is a front view of the table guide structure, and FIG. 3 is a side view of the table guide structure. The guide structures of both drive tables 3 and 4 are substantially the same.
[0026]
The drive tables 3 and 4 are guided to the base 2 in a reciprocating manner by two rows of mountain-shaped slide grooves, that is, VV guide surfaces 40. That is, in FIG. 2, sliding members 41 and 41 having triangular cross sections are attached to the lower surfaces of the left and right ends of the drive tables 3 and 4, respectively, and the lower surfaces of the mountain shapes become the lower sliding surfaces 42 and 42. ing.
[0027]
On the other hand, rail members 46, 46 having a pair of V-shaped grooves are provided on the base 2 with the V-shaped guide surfaces 47, 47 facing upward, and receive the sliding members 41, 41 of the drive table 4. Needle roller bearings 48 and 48 are provided between the V-shaped guide surfaces 47 and 47 and the lower sliding surfaces 42 and 42.
[0028]
The VV guide surface 40 has the advantage that the posture restraint in the direction orthogonal to the reciprocating direction of the drive tables 3 and 4 can be performed with extremely high accuracy, and the needle roller bearing 48 provides high positioning accuracy due to low frictional resistance. Realized.
[0029]
Further, flat upper sliding surfaces 43, 43 are formed on the upper surfaces of the left and right ends of the drive tables 3, 4, respectively, and a pressure oil reservoir for introducing pressure oil to the upper sliding surfaces 43, 43. 44 is formed, and an oil feed passage 45 is formed in the wall thickness of the drive table 4. Then, upper sliding portions 52, 52 having a square cross section are attached to both ends of the base 2 via connecting members 51, 51, and the lower surfaces of the upper sliding surfaces are in contact with the upper sliding surfaces 43, 43. 53, 53. The upper sliding surfaces 53, 53 and the upper sliding surfaces 43, 43 constitute a static pressure guide surface that is in contact with each other via static pressure oil.
[0030]
This static pressure guide surface restricts the vertical orientation of the drive tables 3 and 4 to make the pressure distribution between the base 2 and the drive tables 3 and 4 uniform.
[0031]
As shown in FIGS. 2 to 3, the feed screw 61 that reciprocates the drive tables 3 and 4 is rotatably supported by brackets 62 and 62 on the base 2 via a bearing 63. A nut 60 is screwed onto the feed screw 61, and the nut holder 64 restrains the nut 60 from rotating. A slide shoe 65 is attached to the lower surface of the nut holder 64, and a coupling half 66 constituting a static pressure coupling is formed on the upper surface. The coupling half 66 is formed with static pressure contact surfaces 67 and 67 formed at right angles to and perpendicular to the feed direction of the feed screw 61 on the forward surface and the reverse surface.
[0032]
The coupling half 66 is sandwiched between a pair of coupling members 72, 72 fixed to the drive tables 3, 4, and the inner vertical surface 73 of each coupling member 72 is a static pressure contact surface of the coupling half 66. The oil passage 74 is formed in the wall thickness of the coupling member 72 and the drive table 4 to introduce the hydrostatic oil into the inner vertical surface 73. This static pressure coupling prevents movement errors between the nut 64 and the drive tables 3 and 4.
[0033]
The slide shoe 65 is slidably fitted to a linear ball guide 71 fixed on the base 2 so as to prevent the nut 64 from rotating, thereby causing the nut 64 to reciprocate. The linear ball guide 71 is a rolling guide through which rolling elements circulate, and has an advantage that the friction coefficient on the rolling surface is very small.
[0034]
Due to the above table guide structure, the straightness of the wheel drive table 3 is 0.1 μm horizontal (per 10 mm stroke travel) and 0.1 μm vertical (per 10 mm stroke travel), and the straightness of the dresser drive table 4 is horizontal 0 0.1μm (per 10mm stroke) and vertical 0.2μm (per 10mm stroke) are realized.
[0035]
FIG. 4 is a cross-sectional view showing the wheel bearing 10 and the wheel main shaft 11. The wheel spindle 11 is rotatably supported on the wheel bearing 10 by a precision angular ball bearing 13 and a double row cylindrical roller bearing 14. Further, a tapered hole 15 and a through hole 16 are formed coaxially from the tapered hole 15 to the rear end at the front inside the wheel main shaft 11. A flat belt pulley 36 is attached to the rear end portion of the wheel main shaft 11.
[0036]
A draw bar 17 is inserted into and fixed to the through hole 16, and a collet 18 is attached to the tip thereof. On the other hand, the arbor 31 which is a base metal Wb to be processed for truing or a fitting for the wheel W is also tapered at both ends in the axial direction, and a pull stud 33 is fixed to the tip of the insertion side taper portion 32, and the protrusion side taper. A metal base Wb or a wheel W is fastened to the portion 34 by a nut 35 and is detachably fixed.
[0037]
According to the collet chuck structure described above, when the nut 19 of the draw bar 17 is loosened and pushed into the distal end side, the collet 18 releases the pull stud 33, so that the arbor 31 is removed from the wheel main shaft 11. Conversely, when the arbor 31 is inserted, the draw bar 17 is inserted, the collet 18 is hooked on the pull stud 33 and pulled toward the rear end, and the nut 19 is tightened, the arbor 31 can be fixed to the wheel main shaft 11. For this reason, the base metal Wb or the wheel W can be freely attached to and detached from the arbor 31 by tightening or loosening the nut 35.
[0038]
As described above, the base metal Wb and the wheel W electrodeposited with the CBN abrasive grains can be attached and detached with respect to the wheel main shaft 11 extremely easily, and both of them can be trued on the same machine.
[0039]
FIG. 5 is a cross-sectional view of the dresser bearing 20. The dresser main shaft 21 is rotatably supported on the dresser bearing 20 by a radial / thrust composite hydrostatic oil bearing 23 and a radial hydrostatic oil bearing 24. Each of the hydrostatic bearings 23 and 24 is formed with a hydraulic oil reservoir for collecting the hydrostatic oil with respect to the outer surface of the dresser main shaft 21 and an oil feed passage for sending the hydraulic oil to the hydraulic oil reservoir. The dresser main shaft 21 is supported. With this hydrostatic oil bearing, the static rigidity when a load of 30 kgf is applied to the front shaft end of the dresser main shaft 21 is 2 μm in the radial direction and 1 μm in the axial direction, sufficiently resisting the machining reaction force. Enables ultra-precision grinding. A dresser wheel D is detachably attached to the tip of the dresser main shaft 21 with a nut 37.
[0040]
The configuration of the wheel bearing 10 and the dresser bearing 20 described above is required for micro truing. (1) When the normal resistance during truing is large, the shaft on which the rotary dresser is attached has the same degree of rigidity as the main spindle of the grinding machine, (2) It greatly helps to suppress the runout of the dresser main shaft as much as possible, and (3) to minimize the processing transfer error during truing due to torque fluctuation and vibration of the drive motor.
[0041]
The drive motors 12 and 22 are both of vibration class CLASS3 and can be set to an arbitrary rotational speed up to 3,000 rpm by inverter control. Thereby, by changing the peripheral speed ratio between the wheel W and the dresser D at the time of micro truing, the sharpness and the finished surface roughness can be controlled.
[0042]
The drive motors of the drive tables 3 and 4, that is, the motor connected to the feed screw 61 is a direct drive servo motor with high torque and high accuracy. The control devices for the drive tables 3 and 4 are numerical control devices having a control resolution of 0.01 μm or less, and the laser linear scales 7 and 8 which are feedback sensors of the drive tables 3 and 4 have a minimum resolution of 0.01 μm. The fixed part 7a and the movable part 7b of the laser linear scale 7 and the fixed part 8a and the movable part 8b of the laser linear scale 8 are all arranged at positions according to the Abbe principle. In other words, it follows the principle that the part to be measured is placed on the extension of a standard scale (displacement sensor) that is used as a ruler. In this case, even if there is an error in the straightness of the bed, the resulting geometry The error is very small. The feed amount of the both drive tables, that is, the cut amount of the dresser D with respect to the wheel W is fed back to the numerical control device by the laser linear scales 7 and 8 and is subjected to closed loop control.
[0043]
In the present embodiment, as a measure against thermal displacement, the temperature of the hydrostatic oil and the grinding fluid is controlled within a range of ± 0.1 ° C. by a temperature control device. The grinding fluid also uses a magnetic separator to always provide a clean coolant supply.
[0044]
In the present embodiment, the AE sensor 25 is installed on the dresser bearing 20. This is because in order to realize truing with a minute notch, it is necessary to enable detection of minute contact between the dresser D and the wheel. The AE sensor 25 reliably detects AE waves (acoustic emission waves / shock waves generated at the time of destruction), and determines whether the dresser D hits the base metal Wb or the wheel W (cuts in) or not. It can be detected reliably, and it makes it possible to cut air during microtruing (empty cutting), shorten cycle time, and prevent overcutting.
[0045]
In addition, the dynamic balance of each rotary drive unit including the dresser spindle 21 is adjusted by a field balancer with a resolution of vibration displacement ± 0.001 μm (at 1,200 rpm), and the drive is performed after adjusting the residual unbalance amount to the last digit of the resolution. Yes.
[0046]
About the apparatus of the said structure, the motion response performance in the micro step feed command from a machine NC apparatus was measured with the laser length measuring machine. As a result, as shown in FIG. 6, good data could be obtained up to a minimum step response of 0.05 μm (50 nm) / STEP.
[0047]
According to “Miyashita Masakazu,“ Ultraprecision Machining Principle ”, Superprecision Production Technology, Volume 1, Basic Technology Fujifukuno System, 1995”, to achieve ductile mode grinding using a grinding wheel as a multi-blade tool The variation of the abrasive cutting edge height must be smaller than the ductile / brittle transition point Dc. The ductile / brittle transition point Dc of diamond, silicon, etc., which is said to be a brittle material, is about 0.1 μm. Therefore, in the ultra-precision truing of a diamond wheel, in order to control the abrasive cutting depth, satisfy the ductile mode grinding conditions, and achieve ultra-precise grinding accuracy according to the motion transfer principle, It proposes that ultra-precision truing technology that corrects the variation to 100 nm (0.1 μm) or less and the rotational runout and bus bar shape of the diamond wheel to 100 nm is indispensable.
[0048]
According to the apparatus of the present embodiment, by improving the rigidity on the structural surface and enabling fine feed by the control system, the cutting amount Dp ≦ Dc shown in FIG. 9 is realized, and the nanometer order based on the motion transfer principle Instability of cutting depth Dp caused by movement error (backlash) due to lack of device rigidity shown in FIG. 11 or material removal due to accumulation of cracks generated in the state of cutting depth Dp> Dc shown in FIG. This eliminates the grinding condition such as the cracks caused by grinding and achieves the high positioning accuracy of 0.1 μm or less necessary for ductile mode grinding.
[0049]
Next, the micro truing operation by the truing device will be described.
In the truing apparatus of the present invention, (1) a base metal Wb of a CBN electrodeposition wheel for forming a gear with a shape error of 1 μm or less is manufactured. (2) a CBN electrodeposition wheel in which only one layer of CBN abrasive grains is electrodeposited on the base metal Wb. A high precision and high performance CBN electrodeposition wheel is obtained by the procedure of micro-truing W and realizing submicron level shape error and surface roughness.
[0050]
FIG. 7 is an explanatory view of the truing work of the base metal Wb of (1). The base metal Wb shown in the figure is attached to the wheel main shaft 11 shown in FIGS. 1 and 4, while the base metal Wb and the CBN rotary dresser D are rotated, the wheel drive table 3 is moved in the X-axis direction, and the dresser drive table 4 Is moved in the Z-axis direction.
By this operation, a base metal Wb having a desired shape error is obtained.
[0051]
FIG. 8 is an explanatory view of the truing operation of the wheel W in which the CBN abrasive grains Wg are electrodeposited on the wheel base metal Wb of (2). The wheel W electrodeposited with CBN abrasive grains Wg is also attached to the wheel spindle 11 shown in FIGS. 1 and 4, and the wheel drive table 3 is moved in the X-axis direction while the wheel W and the diamond rotary dresser D are rotated, so that the dresser is driven. The table 4 is moved in the Z-axis direction. By this operation, a wheel W having a shape error and surface roughness on the submicron level is obtained.
[0052]
In the present invention, various gear specifications, corrections, electrodeposition abrasive grain size offsets, etc. are automatically calculated on a personal computer, and a machining NC program is generated and provided with a control thread for transferring to the machine NC device. It is possible to perform micro-truing of a gear forming grinding wheel. Further, not only superabrasive wheels (CBN abrasive grains and diamond abrasive grains) but also microtruing of ordinary grindstones are possible.
[0053]
【The invention's effect】
According to the first aspect of the present invention, distortion due to heat generation of the base is suppressed to prevent a reduction in machining accuracy due to deformation, and a low friction resistance and a horizontal and vertical high-rigidity feed screw are provided in the guide structure of each drive table. Suppresses the nut swing and frictional resistance of the nut, and makes the dresser bearing a hydrostatic oil bearing to increase static rigidity and rotational accuracy, sufficiently increase the rigidity of the truing device, and reduce the movement errors and cracks of the cutting tool. It is possible to perform super-precision grinding mainly from a rigid surface so that no scattering occurs.
[0054]
According to invention of Claim 2, propagation of an external vibration can be interrupted | blocked by a damping table, and the fall of the processing precision by an external vibration can be prevented.
[0055]
According to the third aspect of the invention, the fine torque of 0.1 μm or less necessary for the ductility mode is enabled by the high torque high precision table driving actuator, the high resolution numerical measurement control device and the linear laser scale. Truing is possible.
[0056]
According to invention of Claim 4, the AE wave at the time of crushing of an abrasive grain can be detected reliably, and the air cut at the time of truing, shortening of cycle time, and excessive cutting can be prevented.
[0057]
According to the fifth aspect of the present invention, the arbor can be easily replaced, and truing of various base metals and wheels, and further, truing of the base metal and the wheels on the same machine is enabled.
[Brief description of the drawings]
FIG. 1 is a perspective view of a truing device according to an embodiment of the present invention.
FIG. 2 is a front view of a guide structure for drive tables 3 and 4;
FIG. 3 is a side view of a guide structure for drive tables 3 and 4;
4 is a cross-sectional view showing a wheel bearing 10 and a wheel main shaft 11. FIG.
5 is a cross-sectional view showing a dresser bearing 20 and a dresser main shaft 21. FIG.
6 is a graph showing the feed resolution of the dresser spindle 21. FIG.
FIG. 7 is an explanatory diagram of a truing operation of the base metal Wb.
FIG. 8 is an explanatory diagram of a truing operation of the wheel W.
FIG. 9 is an explanatory diagram of ductile mode grinding.
FIG. 10 is an explanatory diagram of brittle mode grinding.
FIG. 11 is an explanatory diagram of grinding with insufficient apparatus rigidity.
[Explanation of symbols]
2 Base 3 Wheel drive table 4 Dresser drive table 7 Laser linear scale 8 Laser linear scale 10 Wheel bearing 11 Wheel spindle 20 Dresser bearing 21 Dresser spindle 40 V-V guide surface D Dresser W Wheel

Claims (5)

Base and
A wheel drive table that reciprocates in the X-axis direction on the base;
A dresser drive table that reciprocates in the Z-axis direction perpendicular to the X-axis on the base;
A wheel drive comprising a wheel bearing mounted on the wheel drive table, a wheel spindle that is rotatably supported by the wheel bearing and is attached to a truing base or a wheel, and a wheel drive motor that rotates the wheel spindle. And
A dresser bearing mounted on the dresser drive table; a dresser main shaft that is rotatably supported by the dresser bearing and attaches a dresser that is a truing tool; and a dresser drive section that includes a dresser drive motor that rotates the dresser main shaft. Become
The base is made of low thermal expansion cast iron;
The dresser bearing is a hydrostatic oil bearing;
Both the wheel drive table and the dresser drive table are guided at their lower sliding surfaces by a needle roller bearing disposed between a VV guide surface and a VV guide surface formed on the base, and The upper sliding surface is in contact with the static pressure guide surface formed on the base,
Each nut holder of each nut screwed to each feed screw for reciprocating movement of the wheel driving table and reciprocating movement of the dresser driving table is guided by a linear ball guide on the base, and via a static pressure coupling. An ultra-precision truing device for a grinding wheel, wherein the device is coupled to each of the wheel drive table and the dresser drive table. The ultra-precision truing device for a grinding wheel according to claim 1, wherein the base is installed on a vibration damping table. Each drive motor of the wheel drive table and the dresser drive table is a direct drive servomotor,
The control device of each drive motor is a numerical control device having a control resolution of 0.01 μm or less,
3. The ultra-precision truing device for a grinding wheel according to claim 1, wherein the feedback sensors of both the drive tables are linear laser scales having a minimum resolution of 0.01 [mu] m. 4. An ultra-precision truing device for a grinding wheel according to claim 1, wherein an AE sensor is installed on the dresser bearing. An arbor gripping mechanism for mounting a metal base or a wheel to be trued is a pull stud fixed to the arbor and a collet that is built in the wheel main shaft and can be opened and closed from the outside. Or the super precision truing apparatus for grinding wheels of 4.

Images