Gear grinding machine and gear grinding method
By inclining the grinding wheel axis and moving it perpendicularly to the workpiece axis, the machine addresses interference issues in conventional gear grinding, enabling effective grinding of small diameter portions and contributing to gearbox miniaturization.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TECH RES GRP NEXT-GENERATION 3D ADDITIVE MFG TECH COMPREHENSIVE DEV ORG
- Filing Date
- 2024-10-29
- Publication Date
- 2026-05-15
AI Technical Summary
Conventional gear grinding machines require a large movement range of the grinding wheel in the tooth width direction, which can interfere with larger diameter portions of the workpiece, especially in multi-stage gears, limiting their effectiveness in grinding small diameter portions without causing interference.
The gear grinding machine employs a grinding wheel axis inclined relative to the workpiece axis, with synchronized rotation and movement of the wheel along a plane perpendicular to the workpiece axis, allowing for controlled grinding without interference by restricting the wheel's movement range in the axial direction.
This approach enables precise grinding of workpieces with reduced interference, facilitating the grinding of small diameter portions without contacting larger regions, contributing to gearbox miniaturization and efficient use of larger grinding wheel diameters.
Smart Images
Figure 2026078884000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a gear grinding machine and a gear grinding method.
Background Art
[0002] Conventionally, a gear grinding machine for grinding a workpiece to be a gear is known. The gear grinding machine synchronously rotates a workpiece having teeth and a grinding wheel having spiral grooves, and brings the two into contact with each other so that the grooves of the grinding wheel mesh with the teeth of the workpiece. Thereby, the grinding wheel grinds the teeth of the workpiece.
[0003] A conventional gear grinding machine is described in, for example, Patent Document 1.
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In a conventional gear grinding machine, in order to grind the teeth of a workpiece from one end to the other end in the tooth width direction, the grinding wheel is moved in the tooth width direction with respect to the workpiece. That is, in a conventional gear grinding machine, the grinding wheel is moved in a direction parallel to the central axis of the workpiece with respect to the workpiece.
[0005] However, in the conventional grinding method, the movement range of the grinding wheel in the tooth width direction is large. For this reason, for example, when grinding the small diameter portion of a workpiece for a multi-stage gear including a small diameter portion and a large diameter portion, there is a problem that the grinding wheel moving in the tooth width direction interferes with the large diameter portion. Further, in addition to multi-stage gears, the same problem occurs when the workpiece has a portion having a diameter larger than the teeth to be ground.
[0006] Therefore, an object of the present invention is to provide a technique capable of grinding a workpiece while restricting the movement range of the grinding wheel in a direction parallel to the central axis of the workpiece.
Means for Solving the Problems
[0007] The first invention is a gear grinding machine for grinding a workpiece that will become a gear, comprising: a workpiece rotation mechanism for rotating a workpiece having a plurality of teeth on its outer circumference about a workpiece axis which is its central axis; a grinding wheel rotation mechanism for rotating a grinding wheel having spiral grooves on its outer circumference about a grinding wheel axis which is its central axis; and a moving mechanism for moving the grinding wheel relative to the workpiece, wherein the grinding wheel axis is inclined with respect to the workpiece axis, and the workpiece rotation mechanism and the grinding wheel rotation mechanism rotate the workpiece and the grinding wheel synchronously, and the moving mechanism moves the grinding wheel along a plane perpendicular to the workpiece axis, thereby grinding the workpiece.
[0008] The second invention is a gear grinding method for grinding a workpiece that will become a gear, comprising the step of grinding the workpiece by rotating a workpiece having a plurality of teeth on its outer circumference around its central axis, the workpiece axis, and rotating a grinding wheel having spiral grooves on its outer circumference around its central axis, the grinding wheel axis, while moving the grinding wheel relative to the workpiece, wherein the grinding wheel axis is inclined with respect to the workpiece axis, and in the step, the workpiece and the grinding wheel are rotated synchronously, and the grinding wheel is moved along a plane perpendicular to the workpiece axis, thereby grinding the workpiece. [Effects of the Invention]
[0009] According to the first and second inventions, the workpiece can be ground while limiting the range of movement of the grinding wheel in the axial direction of the workpiece. [Brief explanation of the drawing]
[0010] [Figure 1] Figure 1 shows the configuration of a gear grinding machine. [Figure 2] Figure 2 is a flowchart showing the operation flow of a gear grinding machine. [Figure 3] Figure 3 shows the state of the workpiece and grinding wheel in step S4. [Figure 4] Figure 4 shows the state of the workpiece and grinding wheel in step S4. [Figure 5] Figure 5 shows the state of the workpiece and grinding wheel in step S4. [Figure 6] Figure 6 shows the movement of the contact area. [Figure 7] Figure 7 shows the grinding process of a workpiece having a first region and a second region. [Figure 8] Figure 8 is a side view of a modified grinding wheel. [Modes for carrying out the invention]
[0011] <1. Configuration of a gear grinding machine> Figure 1 shows the configuration of a gear grinding machine 1 according to one embodiment. The gear grinding machine 1 is a machine tool that grinds a workpiece 9 that will become a gear.
[0012] The workpiece 9 is substantially cylindrical and has multiple teeth 91 on its outer circumferential surface. Hereinafter, the central axis of the workpiece 9 will be referred to as the "workpiece axis A1". The gear produced by grinding the workpiece 9 is, for example, a helical gear. The workpiece 9 that becomes a helical gear has spiral teeth 91 centered on the workpiece axis A1. However, the gear produced by grinding the workpiece 9 may be other types of gears, such as spur gears.
[0013] As shown in Figure 1, the gear grinding machine 1 comprises a workpiece rotation mechanism 10, a grinding wheel 20, a grinding wheel rotation mechanism 30, a moving mechanism 40, and a control unit 50. The workpiece rotation mechanism 10, the grinding wheel rotation mechanism 30, and the moving mechanism 40 are mounted on a common bed (not shown).
[0014] The workpiece rotation mechanism 10 is a mechanism that rotates the workpiece 9 around the workpiece axis A1. The workpiece rotation mechanism 10 includes a pair of clamps that hold the workpiece 9 and a motor that rotates the clamps. In this embodiment, the workpiece 9 rotates while being held in a position where the workpiece axis A1 is facing vertically. However, the orientation of the workpiece axis A1 does not necessarily have to be vertical.
[0015] The grinding wheel 20 is a tool for grinding the teeth 91 of the workpiece 9. The grinding wheel 20 is substantially cylindrical and has a spiral groove 21 on its outer peripheral surface. Hereinafter, the central axis of the grinding wheel 20 is referred to as the "grinding wheel axis A2".
[0016] The grinding wheel rotation mechanism 30 is a mechanism for rotating the grinding wheel 20 about the grinding wheel axis A2. The grinding wheel rotation mechanism 30 has a tool head that holds the grinding wheel 20 and a motor that rotates the tool head. The grinding wheel 20 is held in a posture in which the grinding wheel axis A2 is inclined with respect to the workpiece axis A1. That is, in the present embodiment, the grinding wheel 20 is held in a posture in which the grinding wheel axis A2 is inclined with respect to the horizontal direction and the vertical direction.
[0017] The moving mechanism 40 is a mechanism for moving the grinding wheel 20 relative to the workpiece 9. The moving mechanism 40 moves the entire grinding wheel 20 and the grinding wheel rotation mechanism 30. The moving mechanism 40 includes a first mechanism for approaching and separating the grinding wheel 20 relative to the workpiece 9, a second mechanism for moving the grinding wheel 20 in the vertical direction, and a third mechanism for moving the grinding wheel 20 in a direction along the grinding wheel axis A2 (hereinafter referred to as the "grinding wheel axis direction"). Each mechanism is realized by, for example, a motor and a ball screw that converts the rotation of the motor into a linear motion. By these first mechanism, second mechanism, and third mechanism, the moving mechanism 40 can move the grinding wheel 20 relative to the workpiece 9 in an arbitrary direction in the three-dimensional space.
[0018] Note that the moving mechanism 40 may have a fourth mechanism for adjusting the inclination angle of the grinding wheel axis A2 with respect to the workpiece axis A1.
[0019] The control unit 50 is a unit that controls the operation of each part of the gear grinding machine 1. The control unit 50 is constituted by, for example, a computer having a processor such as a CPU, a memory such as a RAM, and a storage unit such as a hard disk drive. A computer program for controlling the operation of the gear grinding machine 1 is stored in the storage unit.
[0020] Further, the control unit 50 is communicably connected to the above-described work rotation mechanism 10, grinding wheel rotation mechanism 30, and movement mechanism 40. The control unit 50 controls the operations of these respective units according to the above computer program. Thereby, the grinding process of the work 9 in the gear grinding machine 1 proceeds.
[0021] <2. About the grinding method> Subsequently, a method of grinding the work 9 that becomes a gear by the above-described gear grinding machine 1 will be described. FIG. 2 is a flowchart showing the flow of the operation of the gear grinding machine 1.
[0022] When grinding the work 9, first, the work 9 is set on the gear grinding machine 1 (step S1). The work 9 is held by a pair of clamps of the work rotation mechanism 10. Thereafter, the rotation of the work 9 about the work axis A1 is started by the work rotation mechanism 10 (step S2). Also, the rotation of the grinding wheel 20 about the grinding wheel axis A2 is started by the grinding wheel rotation mechanism 30 (step S3).
[0023] The control unit 50 controls the work rotation mechanism 10 and the grinding wheel rotation mechanism 30 so that the work 9 and the grinding wheel 20 rotate synchronously. Synchronous rotation means that the work 9 and the grinding wheel 20 rotate in a phase that allows them to mesh with each other. The control unit 50 moves the grinding wheel 20 relative to the work 9 by the movement mechanism 40 in a state where the work 9 and the grinding wheel 20 are rotated synchronously by the work rotation mechanism 10 and the grinding wheel rotation mechanism 30 (step S4).
[0024] FIGS. 3, FIG. 4, and FIG. 5 are diagrams showing the states of the work 9 and the grinding wheel 20 in step S4. As shown in FIGS. 3 and FIG. 4, the movement mechanism 40 moves the grinding wheel 20 along a plane perpendicular to the work axis A1. Specifically, the movement mechanism 40 moves the grinding wheel 20 along a linear path L between the first position P1 and the second position P2 shown in FIGS. 3 and FIG. 4. The grinding wheel 20 contacts the work 9 on the path L between the first position P1 and the second position P2. At that time, since the work 9 and the grinding wheel 20 are rotating synchronously, the tooth 91 and the groove 21 contact each other in a meshed state.
[0025] As shown in Figure 3, the grinding wheel spindle A2 is inclined with respect to the workpiece spindle A1. Therefore, the grinding wheel 20 contacts the workpiece 9 only near the point where the workpiece spindle A1 and the grinding wheel spindle A2 intersect in Figure 3. Hereafter, the part where the grinding wheel 20 and the workpiece 9 come into contact will be referred to as the "contact area C". At this contact area C, the teeth 91 of the workpiece 9 and the grooves 21 of the grinding wheel 20 slide against each other at a sliding speed corresponding to the intersection angle θ. As a result, the surface of the teeth 91 of the workpiece 9 is ground.
[0026] The intersection angle θ of the grinding wheel axis A2 with respect to the workpiece axis A1 is preferably, for example, 3° or more and 35° or less. This allows for the generation of an appropriate sliding speed at the contact point C while keeping the intersection angle θ low. Furthermore, it is even more desirable for the intersection angle θ of the grinding wheel axis A2 with respect to the workpiece axis A1 to be 5° or more and 12° or less. This allows for the generation of an even more appropriate sliding speed at the contact point C.
[0027] Figure 6 shows the movement of the contact portion C. As shown in Figure 6, the length d2 of the grinding wheel 20 in the direction parallel to the work axis A1 (hereinafter referred to as the "work axis direction") is longer than the length d1 of the teeth 91 of the workpiece 9 in the work axis direction. More specifically, the length d2 of the portion of the grinding wheel 20 that overlaps with the grinding wheel axis A2 in Figure 6 in the work axis direction is longer than the length d1 of the teeth 91 of the workpiece 9 in the work axis direction. In step S4, as the grinding wheel 20 moves along the path L, the position of the contact portion C moves in the work axis direction, as shown in Figure 6. As a result, the teeth 91 of the workpiece 9 are ground from one end to the other in the work axis direction.
[0028] The gear grinding machine 9 moves the grinding wheel 20 from the first position P1 to the second position P2, and then moves the grinding wheel 20 from the second position P2 to the first position P1 without changing the direction of rotation of the workpiece 9 or the grinding wheel 20. This allows the surface of the teeth 91 of the workpiece 9 to be ground multiple times. In this embodiment, the grinding wheel 20 is moved back and forth between the first position P1 and the second position P2 without changing the direction of rotation of the workpiece 9 or the grinding wheel 20. That is, the grinding wheel 20 repeatedly moves from the first position P1 to the second position P2 and from the second position P2 to the first position P1. As a result, the grinding wheel 20 repeatedly contacts the workpiece 9. Consequently, the surface of the teeth 91 of the workpiece 9 can be sufficiently ground by the grinding wheel 20.
[0029] After moving the grinding wheel 20 back and forth a predetermined number of times, the moving mechanism 40 stops the grinding wheel 20 at the first position P1 or the second position P2. Then, the grinding wheel rotation mechanism 30 stops the rotation of the grinding wheel 20 (step S5), and the workpiece rotation mechanism 10 stops the rotation of the workpiece 9 (step S6). After that, the workpiece 9 is removed from the gear grinding machine 1 (step S7). If the workpiece 9 is automatically replaced by a loader and the next workpiece 9 is to be ground continuously, step S5 above may be omitted and the rotation of the grinding wheel 20 may be continued.
[0030] As described above, in the gear grinding machine 1 of this embodiment, the moving mechanism 40 grinds the workpiece 9 by moving the grinding wheel 20 along a plane perpendicular to the workpiece axis A1, rather than moving the grinding wheel 20 in the workpiece axis direction as in the conventional method. This allows grinding of the workpiece 9 while limiting the range of movement of the grinding wheel 20 in the workpiece axis direction.
[0031] In particular, in the gear grinding machine 1 of this embodiment, the moving mechanism 40 moves the grinding wheel 20 along a straight line tangent to the workpiece 9 on a plane perpendicular to the workpiece axis A1. Moving the workpiece 9 in a straight line in this way makes it easier to control the direction of movement of the grinding wheel 20 than when it is moved in a curved line.
[0032] The gear grinding machine 1 of this embodiment is particularly useful when grinding a workpiece 9 as shown in Figure 7. The workpiece 9 in Figure 7 has a first region 901 and a second region 902. The first region 901 protrudes radially with respect to the workpiece axis A1. The second region 902 protrudes radially with respect to the workpiece axis A1 and has a larger diameter than the first region 901. In the example in Figure 7, the grinding wheel 20 grinds the first region 901 of the workpiece 9. In this case, if the grinding wheel 20 is moved in the direction of the workpiece axis as in the conventional method, the grinding wheel 20 will come into contact with the second region 902 of the workpiece 9. However, in the method of this embodiment, the grinding wheel 20 is moved along a plane perpendicular to the workpiece axis A1. This makes it possible to grind the first region 901 without the grinding wheel 20 coming into contact with the second region 902.
[0033] The workpiece 9 in Figure 7 is, for example, a two-stage gear. In this case, the first region 901 of the workpiece 9 becomes the small-diameter gear of the two-stage gear, and the second region 902 of the workpiece 9 becomes the large-diameter gear of the two-stage gear. In recent years, with the spread of electric vehicles, there has been a demand to manufacture two-stage gears from a single component. Furthermore, in order to miniaturize the gearbox of an electric vehicle, it is necessary to reduce the axial length of the two-stage gear. In this case, the distance between the first region 901 and the second region 902 of the workpiece 9 in the axial direction becomes smaller, making it difficult to grind the first region 901 using conventional methods. However, as described above, according to the method of this embodiment, the first region 901 can be ground without the grinding wheel 20 coming into contact with the second region 902. Therefore, it can contribute to the miniaturization of the gearbox.
[0034] Compared to cutting processes such as shaving, grinding requires a higher peripheral speed of the grinding wheel to achieve good results. Conventional gear grinding machines ensured this peripheral speed by increasing the diameter of the grinding wheel. However, increasing the diameter of the grinding wheel in conventional methods causes the grinding wheel 20 to come into contact with the second region 902 of the workpiece 9, as described above. However, in the method of this embodiment, the intersection angle θ between the workpiece axis A1 and the grinding wheel axis A2 is made smaller than in conventional methods, and the workpiece 9 is moved along a plane perpendicular to the workpiece axis A1. As a result, the diameter of the grinding wheel 20 can be increased to some extent, while grinding the first region 901 without the grinding wheel 20 coming into contact with the second region 902.
[0035] <3. Variant> Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above.
[0036] Figure 8 is a side view of a modified grinding wheel 20. In the above embodiment, the general shape of the outer surface of the grinding wheel 20, ignoring the grooves 21, was a straight cylindrical shape. That is, in the above embodiment, the outer diameter at both ends of the grinding wheel 20 in the grinding wheel axial direction was the same as the outer diameter at the center of the grinding wheel 20 in the grinding wheel axial direction. In contrast, in the example of Figure 8, the general shape of the outer surface of the grinding wheel 20, ignoring the grooves 21, is curved in a drum shape. That is, in the example of Figure 8, the outer diameter at both ends of the grinding wheel 20 in the grinding wheel axial direction is larger than the outer diameter at the center of the grinding wheel 20 in the grinding wheel axial direction. By using such a grinding wheel 20, the amount of grinding at both ends of the workpiece 9 in the workpiece axial direction can be increased.
[0037] Furthermore, in the above embodiment, the moving mechanism 40 moved the grinding wheel 20 along a linear path L. However, the moving mechanism 40 may also move the grinding wheel 20 along a curved path. For example, the moving mechanism 40 may move the grinding wheel 20 along a circular arc inscribed in a plane perpendicular to the workpiece axis A1.
[0038] Furthermore, the elements that appear in the above embodiments and modifications may be combined as appropriate, to the extent that no contradictions arise.
[0039] <4. Summary> This technology can be configured as follows:
[0040] (1) A gear grinding machine for grinding a workpiece that will become a gear, comprising: a workpiece rotation mechanism for rotating a workpiece having a plurality of teeth on its outer circumference about a workpiece axis which is the central axis of the workpiece; a grinding wheel rotation mechanism for rotating a grinding wheel having spiral grooves on its outer circumference about a grinding wheel axis which is the central axis of the grinding wheel; and a moving mechanism for moving the grinding wheel relative to the workpiece, wherein the grinding wheel axis is inclined with respect to the workpiece axis, the workpiece rotation mechanism and the grinding wheel rotation mechanism rotate the workpiece and the grinding wheel synchronously, and the moving mechanism moves the grinding wheel along a plane perpendicular to the workpiece axis, thereby grinding the workpiece.
[0041] (2) A gear grinding machine as described in (1), wherein the moving mechanism moves the grinding wheel along a straight line tangent to the workpiece on the plane.
[0042] (3) A gear grinding machine according to (1) or (2), wherein the length of the grinding wheel in the axial direction of the workpiece is longer than the length of the teeth of the workpiece in the axial direction of the workpiece.
[0043] (4) A gear grinding machine according to any one of (1) to (3), wherein the angle of intersection of the grinding wheel axis with respect to the workpiece axis is 3° or more and 35° or less.
[0044] (5) A gear grinding machine according to any one of (1) to (4), wherein the moving mechanism causes the grinding wheel to reciprocate relative to the workpiece, thereby repeatedly bringing the grinding wheel into contact with the workpiece, without changing the direction of rotation of the workpiece or the direction of rotation of the grinding wheel.
[0045] (6) A gear grinding machine according to any one of (1) to (5), wherein the outer diameter of the grinding wheel at both ends in the axial direction of the grinding wheel is greater than the outer diameter of the grinding wheel at the center in the axial direction of the grinding wheel.
[0046] (7) A gear grinding machine according to any one of (1) to (6), wherein the workpiece has a first region projecting radially with respect to the workpiece axis and a second region projecting radially with respect to the workpiece axis and having a larger diameter than the first region, and the grinding wheel grinds the first region.
[0047] (8) A gear grinding method for grinding a workpiece that will become a gear, comprising the step of grinding the workpiece by rotating a workpiece having a plurality of teeth on its outer circumference about its central axis, the workpiece axis, and rotating a grinding wheel having spiral grooves on its outer circumference about its central axis, the grinding wheel axis, while moving the grinding wheel relative to the workpiece, wherein the grinding wheel axis is inclined with respect to the workpiece axis, and in the step, the workpiece and the grinding wheel are rotated synchronously, and the grinding wheel is moved along a plane perpendicular to the workpiece axis, thereby grinding the workpiece.
[0048] A gear grinding method according to (9)(8), wherein in the step, the grinding wheel is moved along a straight line tangent to the workpiece on the plane.
[0049] A gear grinding method according to (10)(8) or (9), wherein the length of the grinding wheel in the axial direction of the workpiece is longer than the length of the teeth of the workpiece in the axial direction of the workpiece.
[0050] A gear grinding method according to any one of (11)(8) to (10), wherein the angle of intersection of the grinding wheel axis with respect to the workpiece axis is 3° or more and 35° or less.
[0051] A gear grinding method according to any one of (12)(8) to (11), wherein in the step, the grinding wheel is moved back and forth with respect to the workpiece without changing the direction of rotation of the workpiece and the direction of rotation of the grinding wheel, thereby repeatedly bringing the grinding wheel into contact with the workpiece.
[0052] A gear grinding method according to any one of (13)(8) to (12), wherein the outer diameter of the grinding wheel at both ends in the axial direction of the grinding wheel is larger than the outer diameter of the grinding wheel at the center in the axial direction of the grinding wheel.
[0053] A gear grinding method according to any one of (14)(8) to (13), wherein the workpiece has a first region projecting radially with respect to the workpiece axis and a second region projecting radially with respect to the workpiece axis and having a larger diameter than the first region, and the grinding wheel grinds the first region. [Industrial applicability]
[0054] This invention can be used in gear grinding machines and gear grinding methods. [Explanation of Symbols]
[0055] 1: Gear grinding machine 9: Work 10: Workpiece rotation mechanism 20: Sharpening stone 21: Groove 30: Grinding wheel rotation mechanism 40: Movement mechanism 50: Control Unit 91: Teeth 901 :1st area 902:Second area A1: Work axis A2: Grinding wheel shaft C: Contact part L: Route P1: 1st position P2: 2nd position θ: Crossing angle
Claims
1. A gear grinding machine for grinding workpieces that will become gears, A workpiece rotation mechanism that rotates a workpiece having multiple teeth on its outer surface around its central axis, the workpiece axis, A grinding wheel rotation mechanism that rotates a grinding wheel having spiral grooves on its outer surface around its central axis, the grinding wheel axis, A moving mechanism for moving the grinding wheel relative to the workpiece, Equipped with, The grinding wheel axis is inclined with respect to the workpiece axis, A gear grinding machine in which the workpiece rotation mechanism and the grinding wheel rotation mechanism rotate the workpiece and the grinding wheel synchronously, and the moving mechanism moves the grinding wheel along a plane perpendicular to the workpiece axis, thereby grinding the workpiece.
2. A gear grinding machine according to claim 1, The aforementioned moving mechanism is a gear grinding machine that moves the grinding wheel along a straight line tangent to the workpiece on the plane.
3. A gear grinding machine according to claim 1 or claim 2, A gear grinding machine wherein the length of the grinding wheel in the axial direction of the workpiece is longer than the length of the teeth of the workpiece in the axial direction of the workpiece.
4. A gear grinding machine according to claim 1 or claim 2, A gear grinding machine in which the angle of intersection of the grinding wheel axis with respect to the workpiece axis is 3° or more and 35° or less.
5. A gear grinding machine according to claim 1 or claim 2, A gear grinding machine in which the moving mechanism causes the grinding wheel to reciprocate relative to the workpiece, thereby repeatedly bringing the grinding wheel into contact with the workpiece, without changing the direction of rotation of the workpiece or the direction of rotation of the grinding wheel.
6. A gear grinding machine according to claim 1 or claim 2, A gear grinding machine wherein the outer diameter of the grinding wheel at both ends in the axial direction of the grinding wheel is larger than the outer diameter of the grinding wheel at the center in the axial direction of the grinding wheel.
7. A gear grinding machine according to claim 1 or claim 2, The aforementioned workpiece is A first region projecting radially with respect to the workpiece axis, A second region that protrudes radially with respect to the workpiece axis and has a larger diameter than the first region, It has, The grinding wheel is a gear grinding machine that grinds the first region.
8. A gear grinding method for grinding a workpiece that will become a gear, The process involves rotating a workpiece having multiple teeth on its outer surface around its central axis, the workpiece axis, and moving a grinding wheel having spiral grooves on its outer surface around its central axis, the grinding wheel axis, while simultaneously grinding the workpiece. The grinding wheel axis is inclined with respect to the workpiece axis, A gear grinding method comprising the steps described above, in which the workpiece and the grinding wheel are rotated synchronously, and the grinding wheel is moved along a plane perpendicular to the workpiece axis, thereby grinding the workpiece.
9. A gear grinding method according to claim 8, A gear grinding method comprising the step of moving the grinding wheel along a straight line tangent to the workpiece on the plane.
10. A gear grinding method according to claim 8 or claim 9, A gear grinding method wherein the length of the grinding wheel in the axial direction of the workpiece is longer than the length of the teeth of the workpiece in the axial direction of the workpiece.
11. A gear grinding method according to claim 8 or claim 9, A gear grinding method wherein the angle of intersection of the grinding wheel axis with respect to the workpiece axis is 3° or more and 35° or less.
12. A gear grinding method according to claim 8 or claim 9, A gear grinding method comprising the above step, in which the grinding wheel is moved back and forth against the workpiece without changing the direction of rotation of the workpiece and the direction of rotation of the grinding wheel, thereby repeatedly bringing the grinding wheel into contact with the workpiece.
13. A gear grinding method according to claim 8 or claim 9, A gear grinding method wherein the outer diameter of the grinding wheel at both ends in the axial direction of the grinding wheel is larger than the outer diameter of the grinding wheel at the center in the axial direction of the grinding wheel.
14. A gear grinding method according to claim 8 or claim 9, The aforementioned workpiece is A first region projecting radially with respect to the workpiece axis, A second region that protrudes radially with respect to the workpiece axis and has a larger diameter than the first region, It has, The grinding wheel is used to grind the first region, and the method is gear grinding.