JP4981769B2 - Thread grinding wheel phasing device - Google Patents

Description

  The present invention relates to a phase adjusting device for a threaded grindstone that performs phase alignment of a threaded grindstone with respect to a workpiece gear or a dresser prior to meshing between the threaded grindstone and a workpiece gear or a dresser during grinding or dressing.

  2. Description of the Related Art Conventionally, a gear grinder has been provided as one that grinds a workpiece, which is a gear to be processed after heat treatment, using a grindstone, which is a grinding tool, and efficiently finishes the tooth surface of the workpiece. In such a gear grinding machine, the grindstone and the workpiece are meshed with each other and the workpiece is ground by rotating them synchronously. If the meshing accuracy becomes insufficient, uneven grinding may occur on the tooth surface of the workpiece. In addition, an excessive load is applied to the grindstone, which may shorten the life of the grindstone.

  Therefore, in this type of gear grinding machine, in order to mesh the grinding wheel and the workpiece with high precision, the grinding wheel cutting edge (mountain valley) and the work tooth groove (mountain valley) are formed prior to meshing during grinding. Phase alignment is performed to position both phases so as to obtain an appropriate phase relationship. Such a phase alignment device that performs phase alignment between a grindstone and a workpiece is disclosed in Patent Document 1, for example.

Japanese Patent Laid-Open No. 5-138438

  In the conventional phasing device described above, the grinding wheel is slid in the axial direction on the workpiece, and the moment when the grinding wheel crosses the thread groove of the workpiece and the moment when the grinding wheel becomes non-contact are detected by the AE sensor. The phase of the grindstone and the workpiece is adjusted by moving the workpiece in the axial direction so that the grindstone faces the middle position of the thread groove obtained based on the detection result.

  However, in such a conventional configuration, since the contact and non-contact of the grindstone with the workpiece are determined by detecting the vibration of the workpiece at the time of contact by the AE sensor, the wheel grinding capable of dressing the grindstone on the machine is performed. In the board, another AE sensor is required for phase matching between the grindstone and the dresser. As a result, the apparatus may be complicated.

  Therefore, the present invention solves the above-mentioned problem, and provides a phase adjusting device for a threaded grindstone capable of precisely performing phase alignment of a threaded grindstone with respect to a workpiece gear or a dresser with a simple configuration. With the goal.

A phase adjusting device for a threaded grindstone according to the present invention that solves the above problems is as follows.
Prior to meshing of the threaded grinding wheel and the workpiece gear during grinding, a phase adjusting device for the threaded grinding wheel for phase matching the threaded grinding wheel with respect to the workpiece gear ,
A detecting means that is provided on a grindstone head that rotatably supports the threaded grindstone, and detects whether the threaded grindstone is in contact with a workpiece gear ;
Based on the phase of the threaded grindstone when the detecting means detects contact, and comprises a grindstone phase control means for positioning the threaded grindstone in a engageable phase ,
The detection means includes
An acoustic emission type fluid sensor that detects an elastic wave of the threaded grinding wheel caused by vibration or friction via a fluid jetted in the vicinity of the threaded grinding wheel,
By injecting the fluid at any position where the phase is shifted by 90 ° in the circumferential direction of the threaded grindstone from the contact position between the threaded grindstone and the work gear depending on whether the work gear is right-handed or left-handed, According to the detected elastic wave, it is detected whether or not the threaded grindstone is in contact with the gear to be processed .

  According to the phase adjusting device for a threaded grindstone according to the present invention, whether or not the threaded grindstone is in contact with the workpiece gear or the dresser is detected by the detecting means provided on the grindstone head that rotatably supports the threaded grindstone. By detecting, the phase alignment of the threaded grinding wheel with respect to the workpiece gear or the dresser can be precisely performed with a simple configuration.

  Hereinafter, a phase adjusting device for a threaded grindstone according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of a phase adjusting device for a threaded grindstone according to an embodiment of the present invention, and shows a state when a threaded grindstone is dressed by a disk dresser, and FIG. FIG. 3 is a diagram showing a state of grinding with a grindstone, FIG. 3 is a diagram showing a mounting structure of an AE fluid sensor, FIG. 4 is a diagram showing an installation position of the AE fluid sensor with respect to a screw-shaped grindstone at the time of grinding, and FIG. FIG. 6 is a diagram showing a set position of the AE fluid sensor with respect to the threaded grindstone in FIG. 6, and FIG. 6 is a diagram showing a change in voltage when the AE fluid sensor detects an elastic wave of the threaded grindstone.

  As shown in FIG. 2, the gear grinding machine 1 to which the phase adjusting device for a threaded grinding wheel according to the present invention is applied, grinds a workpiece (workpiece gear) W of an internal gear material with a barrel-shaped threaded grinding wheel 14. Further, as shown in FIG. 1, it has a dressing function for dressing the threaded grindstone 14 with a disk dresser 32.

  As shown in FIGS. 1 to 3, a wheel head 11 is supported on the gear grinding machine 1 so as to be movable and turnable. A spindle 12 is rotatably supported by the grindstone head 11, and a grindstone arbor 13 is formed at the tip of the spindle 12. A threaded grindstone 14 is detachably attached to the tip of the grindstone arbor 13. That is, by driving the grindstone head 11, the threaded grindstone 14 is rotationally driven via the grindstone arbor 13 of the spindle 12.

  A rotary table 21 is rotatably supported on the front surface of the grindstone head 11, and a workpiece W is detachably attached to the upper surface of the rotary table 21 via a mounting jig (not shown). That is, by driving the rotary table 21, the workpiece W is rotationally driven.

  A dresser driving unit 31 is movably supported on the side of the rotary table 21, and a disk dresser 32 is rotatably attached to the dresser driving unit 31 in a detachable manner. That is, by driving the dresser driving unit 31, the disk dresser 32 is rotationally driven.

An acoustic emission type AE (Acoustic Emission) fluid sensor (detection means, fluid sensor) 42 is supported via a bracket 41 on the front end surface of the grindstone head 11. The AE fluid sensor 42 detects an elastic wave caused by vibration or friction generated in the material through the injected fluid, and processes this as an AE signal. It has an injection hole 42a for injecting it to a predetermined measurement position of the arbor 13, and a detector 42b for detecting an elastic wave propagated from the measurement position via the coolant C. Further, a coolant tank 43 is connected to the injection hole 42a of the AE fluid sensor 42, and an AE sensor amplifier 44 is connected to the detection portion 42b.

As shown in FIG. 4, the AE fluid sensor 42 is installed at a position where the phase is shifted by 90 ° in the circumferential direction of the threaded grinding wheel 14 from the contact position between the threaded grinding wheel 14 and the workpiece W. Therefore, the coolant C is sprayed toward the measurement position of the grindstone arbor 13. That is, at the time of phase alignment of the threaded grindstone 14 with respect to the work W, the grindstone arbor 13 is moved from a direction in which the phase is shifted by 90 ° in the circumferential direction of the threaded grindstone 14 from the contact position between the threaded grindstone 14 and the work W. The coolant C is injected toward the measurement position. If it is determined in which direction the installation position of the AE fluid sensor 42 is shifted depending on whether the workpiece W is twisted to the right or to the left, the grindstone head 11 (thread-like shape) is used when the threaded grindstone 14 and the workpiece W are engaged. Even if the grindstone 14) turns and tilts, the AE fluid sensor 42 does not interfere with the workpiece W.

Further, as shown in FIG. 5, at the time of phase adjustment of the threaded grindstone 14 with respect to the disk dresser 32, the AE fluid sensor 42 moves from the contact position between the threaded grindstone 14 and the disk dresser 32 in the circumferential direction of the threaded grindstone 14. The coolant C is injected toward the measurement position of the grindstone arbor 13 from the direction in which the phase is shifted by 90 °.

  The coolant C supplied from the coolant tank 43 to the AE fluid sensor 42 is, for example, grinding oil, and the coolant pressure and the injection flow rate can be adjusted according to the distance between the AE fluid sensor 42 and the measurement position. It has become.

  That is, in the AE fluid sensor 42, the coolant C supplied from the coolant tank 43 is sprayed from the spray hole 42a to the measurement position of the grindstone arbor 13, so that the generated elastic wave of the threaded grindstone 14 is passed through the coolant C. Then, the detected elastic wave is input to the AE sensor amplifier 44 as an AE signal. As shown in FIG. 6, the AE sensor amplifier 44 converts the inputted AE signal into a voltage V and displays it as needed.

  Further, the gear grinding machine 1 is provided with an NC device (grinding wheel phase control means) 50. The NC device 50 is connected to, for example, the grindstone head 11, the rotary table 21, the dresser driving unit 31, the AE sensor amplifier 44, and the like, and based on the input workpiece specifications and processing conditions, the threaded grindstone 14 is used. The grinding of the workpiece W and the dressing of the threaded grinding wheel 14 by the disk dresser 32 are controlled, and the magnitude of the elastic wave detected by the AE fluid sensor 44 prior to the meshing (toothing) at the time of grinding or dressing. Based on this, the contact and non-contact between the threaded grinding wheel 14 and the workpiece W or the disk dresser 32 are determined, and the phase of the threaded grinding wheel 14 is adjusted.

  Therefore, when grinding the workpiece W with the threaded grindstone 14, first, as shown in FIG. 2, the threaded grindstone 14 is moved to the workpiece W side attached to the rotary table 21. Next, before the threaded grindstone 14 and the workpiece W are engaged with each other, the phase alignment of these components is roughly performed (coarse phase alignment) so that the cutting edge of the threaded grindstone 14 and the tooth tip of the workpiece W do not interfere with each other. desirable. And in such a rough phase alignment state, while rotating the screw-shaped grindstone 14 and the workpiece | work W synchronously, the coolant C is injected toward the measurement position of the grindstone arbor 13 from the injection hole 42a of the AE fluid sensor 42, and the detection is carried out. Detection of the elastic wave of the threaded grinding wheel 14 is started by the part 42b.

  Thus, when the detection of the elastic wave by the AE fluid sensor 42 is started, the AE sensor amplifier 44 converts the inputted AE signal into a voltage V as shown in FIG. Change will be displayed. At the same time as the detection of elastic waves by the AE fluid sensor 42 is started, the voltage V is measured as the maximum voltage Vf when the threaded grindstone 14 is not in contact, and a threshold value Vo greater than this voltage Vf is automatically set. It is set up. This threshold value Vo is used when determining the contact of the threaded grindstone 14 described later.

  Next, by increasing only the rotation speed (number of rotations) of the workpiece W, the synchronous rotation of the threaded grinding wheel 14 and the workpiece W is shifted, and one tooth surface of the workpiece W is brought into contact with one blade surface of the threaded grinding wheel 14. Let As a result, the elastic wave of the threaded grindstone 14 generated by the contact is transmitted to the grindstone arbor 13, and the elastic wave transmitted to the grindstone arbor 13 is detected by the AE fluid sensor 42 via the coolant C. . At this time, as shown in FIG. 6, in the AE sensor amplifier 44, the waveform of the voltage V changes according to the input AE signal, and this voltage V (Vf) is set to a preset threshold value Vo. If it exceeds, it will determine with the NC apparatus 50 having contacted the workpiece | work W with the threaded grindstone 14, and the phase of the threaded grindstone 14 at this time will be memorize | stored.

  Further, by reducing only the rotation speed (the number of rotations) of the workpiece W, the synchronous rotation of the threaded grinding wheel 14 and the workpiece W is shifted, and the other tooth surface of the workpiece W is brought into contact with the other blade surface of the threaded grinding wheel 14. Let As a result, the elastic wave of the threaded grindstone 14 generated by the contact is transmitted to the grindstone arbor 13, and the elastic wave transmitted to the grindstone arbor 13 is detected by the AE fluid sensor 42 via the coolant C. . At this time, as shown in FIG. 6, in the AE sensor amplifier 44, the waveform of the voltage V changes according to the input AE signal, and this voltage V (Vf) is set to a preset threshold value Vo. If it exceeds, it will determine with the NC apparatus 50 having contacted the workpiece | work W with the threaded grindstone 14, and the phase of the threaded grindstone 14 at this time will be memorize | stored.

  Then, after the intermediate phase, which is an intermediate phase, is obtained from the stored phase of the two threaded grindstones 14 by the NC device 50, the phase of the threaded grindstone 14 is positioned at the intermediate phase, Phase alignment is performed precisely (precise phase alignment). Next, the tooth surface of the workpiece W is ground by the blade surface of the threaded grinding wheel 14 by meshing the threaded grinding wheel 14 with the workpiece W and rotating them synchronously in such a precise phase alignment state. .

  Here, when a predetermined number of workpieces W are ground using the threaded grindstone 14, the blade surface is worn and the sharpness is lowered. Therefore, the threaded grindstone 14 is periodically dressed by the disk dresser 32.

  Therefore, when dressing the threaded grindstone 14 with the disk dresser 32, first, as shown in FIG. 1, after the threaded grindstone 14 is moved to the disk dresser 32 side, before the meshing, It is desirable to roughly perform the phase alignment (coarse phase alignment) so that the blade edge of the grindstone 14 and the blade edge of the disk dresser 32 do not interfere with each other. Next, in such a rough phase alignment state, the disk dresser 32 is rotated while the rotation of the threaded grindstone 14 is stopped, and the coolant C is directed from the injection hole 42a of the AE fluid sensor 42 toward the measurement position of the grindstone arbor 13. The detection of the elastic wave of the threaded grindstone 14 is started by the detecting portion 42b.

  Thus, when the detection of the elastic wave by the AE fluid sensor 42 is started, the AE sensor amplifier 44 converts the inputted AE signal into a voltage V as shown in FIG. Change will be displayed. At the same time as the detection of elastic waves by the AE fluid sensor 42 is started, the voltage V is measured as the maximum voltage Vf when the threaded grindstone 14 is not in contact, and a threshold value Vo greater than this voltage Vf is automatically set. It is set up. This threshold value Vo is used when determining the contact of the threaded grindstone 14 described later.

  Then, the threaded grindstone 14 is rotated forward so that one blade surface thereof is brought into contact with one blade surface of the disk dresser 32. As a result, the elastic wave of the threaded grindstone 14 generated by the contact is transmitted to the grindstone arbor 13, and the elastic wave transmitted to the grindstone arbor 13 is detected by the AE fluid sensor 42 via the coolant C. . At this time, as shown in FIG. 6, in the AE sensor amplifier 44, the waveform of the voltage V changes according to the input AE signal. When the voltage V exceeds a preset threshold value Vo, The NC device 50 determines that the threaded grindstone 14 has contacted the disk dresser 32, and the phase of the threaded grindstone 14 at this time is stored.

  Next, the threaded grindstone 14 is reversed to bring the other blade surface into contact with the other blade surface of the disk dresser 32. As a result, the elastic wave of the threaded grindstone 14 generated by the contact is transmitted to the grindstone arbor 13, and the elastic wave transmitted to the grindstone arbor 13 is detected by the AE fluid sensor 42 via the coolant C. . At this time, as shown in FIG. 6, in the AE sensor amplifier 44, the waveform of the voltage V changes according to the input AE signal. When the voltage V exceeds a preset threshold value Vo, The NC device 50 determines that the threaded grindstone 14 has contacted the disk dresser 32, and the phase of the threaded grindstone 14 at this time is stored.

  Then, after the intermediate phase, which is an intermediate phase, is obtained from the stored phase of the two threaded grindstones 14 by the NC device 50, the phase of the threaded grindstone 14 is positioned at the intermediate phase, Phase alignment is performed precisely (precise phase alignment). Next, in such a precise phase alignment state, the threaded grindstone 14 is engaged with the disk dresser 32 and the disk dresser 32 is rotated, whereby the blade surface of the threaded grindstone 14 is dressed by the blade surface of the disk dresser 32. It will be.

  In the present embodiment, the work W made of the internal gear material is adopted, but a work made of the external gear material may be adopted. Moreover, although the threshold value of the voltage used for the contact determination with the thread-shaped grindstone 14 and the workpiece | work W or the disk dresser 32 was made into the common threshold value Vo, the threshold value of a different value may be used respectively, and these threshold values are each material. It is also possible to set according to the processing conditions.

  Therefore, according to the phase adjusting device for the thread-shaped grindstone according to the present invention, the thread-shaped grindstone 14 with respect to the workpiece W or the disk dresser 32 prior to meshing between the thread-shaped grindstone 14 and the workpiece W or the disk dresser 32 during grinding or dressing. When phase adjustment of the grindstone 14 is performed, it is detected whether the thread-shaped grindstone 14 has contacted the workpiece W or the disk dresser 32 by an AE fluid sensor 42 provided on the grindstone head 11 that rotatably supports the thread-shaped grindstone 14. Then, based on the phase of the threaded grindstone 14 when contact is detected, the threaded grindstone 14 is positioned in a phase that allows the threaded grindstone 14 to mesh. Thereby, the phase alignment of the thread-shaped grindstone 14 with respect to the workpiece | work W or the disk dresser 32 can be precisely performed with a simple structure.

  The present invention is applicable to a gear grinding machine that shortens the non-processing time.

It is a schematic block diagram of the phase alignment apparatus of the thread-shaped grindstone which concerns on one Example of this invention, Comprising: It is the figure which showed a mode when dressing a thread-shaped grindstone with a disk dresser. It is the figure which showed the mode when grinding a workpiece | work with a screw-shaped grindstone. It is the figure which showed the attachment structure of the AE fluid sensor. It is the figure which showed the installation position of the AE fluid sensor with respect to the screw-shaped grindstone at the time of grinding. It is the figure which showed the setting position of the AE fluid sensor with respect to the screw-shaped grindstone at the time of dressing. It is the figure which showed the change of the voltage when the AE fluid sensor detects the elastic wave of a screw-shaped grindstone.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gear grinding machine 11 Grinding wheel head 12 Spindle 13 Grinding wheel arbor 14 Threaded grinding wheel 21 Rotating table 31 Dresser drive part 32 Disk dresser 41 Bracket 42 AE fluid sensor 42a Injection hole 42b Detection part 43 Coolant tank 44 AE sensor amplifier 50 NC apparatus W Workpiece C Coolant V Measured voltage Vo Voltage threshold Vf Maximum voltage without contact

Claims (1)

Prior to meshing of the threaded grinding wheel and the workpiece gear during grinding, a phase adjusting device for the threaded grinding wheel for phase matching the threaded grinding wheel with respect to the workpiece gear ,
A detecting means that is provided on a grindstone head that rotatably supports the threaded grindstone, and detects whether the threaded grindstone is in contact with a workpiece gear ;
Based on the phase of the threaded grindstone when the detecting means detects contact, and comprises a grindstone phase control means for positioning the threaded grindstone in a engageable phase ,
The detection means includes
An acoustic emission type fluid sensor that detects an elastic wave of the threaded grinding wheel caused by vibration or friction via a fluid jetted in the vicinity of the threaded grinding wheel,
By injecting the fluid at any position where the phase is shifted by 90 ° in the circumferential direction of the threaded grindstone from the contact position between the threaded grindstone and the work gear depending on whether the work gear is right-handed or left-handed, A phase adjusting apparatus for a threaded grinding wheel, characterized by detecting whether or not the threaded grinding wheel is in contact with a workpiece gear according to the detected elastic wave .

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