Honing machining device

Abstract

A honing device is provided with: a honing tool (1); a rotating spindle (2) to which the honing tool (1) is fixed; an axial direction drive unit (4) that moves the rotating main shaft (2) in the Z-axis direction; a workpiece holder (3) that holds the workpiece (W) in a state in which the center axis (J2) of the machining hole (Wh) of the workpiece (W) coincides with the center axis (J1) of the rotating spindle (2); and a holder drive unit (6) that moves the workpiece holder (3) in the direction along the central axis (J1) by applying a drive force in the direction along the central axis (J1) to a portion of the workpiece holder (3) that corresponds to an extension line of the central axis (J1) of the rotating main shaft (2).

Description

Technical Field

[0001] The invention relates to a honing device. Background Art

[0002] The following high-speed honing machine has been proposed, that is, it has a spindle that is driven to rotate while holding a honing tool and a workpiece holder that holds a workpiece and is driven by a linear motor in a manner of vibrating in the vertical up and down direction. By driving the spindle in a manner of vibrating in the vertical direction and driving the workpiece holder that holds the workpiece in a manner of vibrating in the vertical direction, it is possible to increase the relative speed of the honing tool in the vertical direction with respect to the workpiece and shorten the processing time (for example, refer to patent document 1). In this high-speed honing machine, the long stator of the linear motor is arranged in a manner that its length direction is along the vertical direction, and the workpiece holder fixed to the rotor of the linear motor is arranged on the side of the stator.

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: European Patent No. 2374574 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, in the high-speed honing machine described in Patent Document 1, when honing a workpiece, the driving force acts on the rotor from the position where the stator acts in a direction orthogonal to the vertical direction and the position where the force caused by the friction resistance between the workpiece held on the workpiece holder and the honing tool acts is offset. Therefore, in particular, when the force caused by the friction resistance acts vertically downward, there is a situation in which the gravity applied to the workpiece holder forms a resultant force, and a force is generated in a direction of rotation with the rotor as a fulcrum relative to the workpiece holder fixed on the rotor, and the workpiece holder is tilted relative to the rotor. In this case, the center axis of the workpiece processing hole is tilted relative to the vertical direction, and there is a risk that the processing accuracy of the workpiece is reduced.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a honing device capable of improving the machining accuracy of a workpiece while shortening the machining time of the workpiece.

[0009] Means to solve the problem

[0010] In order to achieve the above-mentioned purpose, the honing processing device of the present invention comprises a honing tool, a spindle, a rotation drive unit, an axial direction drive unit, a workpiece holder and a holder drive unit, wherein the honing tool is provided with a grindstone at the front end portion; the spindle is a long spindle, and the honing tool is fixed in a state where the front end portion of the honing tool extends from one end side in the length direction; the rotation drive unit rotates the spindle around a first rotation axis along the length direction of the spindle; the axial direction drive unit moves the spindle in a first direction along the first rotation axis; the workpiece holder holds the workpiece in a state where the center axis of the machining hole of the workpiece is consistent with the first rotation axis; the holder drive unit moves the workpiece holder in a second direction opposite to the first direction by applying a driving force to a portion of the workpiece holder corresponding to the extension line of the first rotation axis in the direction along the first rotation axis.

[0011] Effects of the Invention

[0012] According to the present invention, the axial direction driving unit moves the main shaft to which the honing tool is fixed in a first direction along the first rotation axis of the main shaft. In addition, the holder driving unit moves the workpiece holder in a second direction opposite to the first direction by applying a driving force to a portion of the main shaft in the workpiece holder corresponding to the extension line of the first rotation axis in the direction along the first rotation axis. Thus, during the honing process of the workpiece, the relative speed of the honing tool relative to the workpiece can be increased, so the processing time of the workpiece can be shortened. In addition, during the honing process of the workpiece, the position where the holder driving unit applies the driving force to the workpiece holder in the direction along the first rotation axis of the main shaft can be made consistent with the position where the force caused by the friction resistance between the workpiece held on the workpiece holder and the honing tool acts. Therefore, since the occurrence of the force acting in the inclined direction of the workpiece holder is suppressed, the central axis of the workpiece processing hole can be suppressed from tilting relative to the first rotation axis direction, so that the processing accuracy of the workpiece is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view of a honing device according to an embodiment of the present invention.

[0014] Figure 2 It is a side view of the honing apparatus according to the embodiment.

[0015] Figure 3 It is a side view of a part of the honing device according to the embodiment.

[0016] Figure 4 A part of the honing device according to the embodiment Figure 3 Section view along line AA.

[0017] Figure 5A It is a cross-sectional view of a workpiece holder according to the embodiment.

[0018] Figure 5B The workpiece holder according to the embodiment Figure 5A Section view along the BB line.

[0019] Fig. 6A This is a cross-sectional view showing a state in which a holder support body is arranged at a lower limit position of the holder driving unit according to the embodiment.

[0020] Figure 6B This is a cross-sectional view showing a state in which a holder support body is arranged at an upper limit position of the holder driving unit according to the embodiment.

[0021] Fig. 7A This is a diagram showing a state in which the bed is arranged at the upper limit position during machining and the workpiece holder is arranged at the lower limit position during machining in the honing apparatus according to the embodiment.

[0022] Figure 7B This is a diagram showing a state in which the bed is arranged at the lower limit position during machining and the workpiece holder is arranged at the upper limit position during machining in the honing apparatus according to the embodiment.

[0023] Fig. 8A It is a diagram showing vibration waveforms of a bed and a workpiece holder of a honing device according to an embodiment.

[0024] Figure 8B It is a diagram showing vibration waveforms of the bed and the workpiece holder when the amplitude of the workpiece holder of the honing device according to the embodiment is reduced.

[0025] Fig. 9 It is a side view of a part of the honing device related to the comparative example.

[0026] Fig.10 It is a perspective view of a honing device according to a modified example.

[0027] Fig.11 It is a side view of a honing device according to a modified example. DETAILED DESCRIPTION

[0028] Modes for carrying out the invention

[0029] Hereinafter, a honing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1The honing device according to the present embodiment includes a honing tool, a spindle, a rotation drive unit, and an axial drive unit. The honing tool is provided with a grindstone at the front end. The spindle is a long spindle that fixes the honing tool in a state where the front end of the honing tool extends from one end side in the length direction. The rotation drive unit rotates the spindle around a rotation axis along the length direction of the spindle. The axial drive unit moves the spindle in a first direction along the rotation axis. In addition, the honing device includes a workpiece holder and a holder drive unit. The workpiece holder holds the workpiece in a state where the center axis of the machining hole of the workpiece is consistent with the rotation axis of the spindle. The holder drive unit moves the workpiece holder in a second direction opposite to the first direction by applying a driving force to a portion of the workpiece holder corresponding to the extension line of the rotation axis in the direction along the rotation axis.

[0030] like Figure 1 As shown, the honing processing device related to the present embodiment is a device for processing the inner wall of a processing hole of a workpiece, and is equipped with a honing tool 1; a rotating spindle 2; a workpiece holder 3; a holder driving unit 6 and a body 9 that support the workpiece holder 3 and drive the workpiece holder 3 in a manner of vibrating in the Z-axis direction. Hereinafter, in this specification, the vertical up and down directions are expressed as ±Z directions or Z-axis directions, and the directions orthogonal to the vertical directions and mutually orthogonal are expressed as ±X directions, ±Y directions or X-axis directions, and Y-axis directions, respectively. In addition, the honing processing device, such as Figure 2 As shown, it includes a rotation drive unit 5; an axial drive unit 4; an expansion drive unit 8; a holder drive unit 6; a rotation drive unit 5; and a control unit 10 that controls the operation of the axial drive unit 4 and the expansion drive unit 8. Figure 2 In the embodiment, the workpiece W is arranged in a posture that the central axis J2 of the processing hole Wh is consistent with the central axis J1 of the rotating spindle 2. The machine body 9 has a base 92, a bed 93 and a support column 91. The base 92 supports the component holder 3 and the holder drive unit 6; the bed 93 collectively holds the honing tool 1, the rotating spindle 2, the rotating drive unit 5, the axial direction drive unit 4 and the expansion drive unit 8; and the support column 91 is upright on the base 92 to support the bed 93. The support column 91 is a long support column, and is arranged in a posture that its length direction is along the vertical direction, that is, the Z-axis direction, and supports the bed 93 at the end on the vertical upper side.

[0031] The honing tool 1 has a tool body 11 and a plurality of grindstones 12. The tool body 11 is long and cylindrical and is replaceably mounted on the rotating spindle 2 in a manner extending from the lower end 2a of the rotating spindle 2 in the -Z direction. The plurality of grindstones 12 are arranged at the end of the tool body 11 in the -Z direction so as to be expandable and contractible in the radial direction of the tool body 11. In addition, the honing tool 1 has a wedge rod (not shown) and a loading member (not shown). The wedge rod has a wedge portion (not shown) arranged at the end in the -Z direction. The wedge portion is arranged in a state of contact with an inclined surface of a grindstone table (not shown) on the inner side of the tool body 11 to which the grindstone 12 is fixed, which is opposite to the grindstone 12 side, and is used to expand and move the grindstone 12 by relative movement in the vertical direction relative to the tool body 11. The loading member loads the grindstone 12 in the direction of contraction. The wedge rod is connected to the expansion rod 87 described later, which is arranged on the +Z direction side of the wedge rod inside the rotating spindle 2. In addition, the grindstone 12 is normally loaded in the contraction direction by the above-mentioned loading member. As a result, the grindstone table and the grindstone 12 fixed on the grindstone table are pushed by the wedge portion to move in the expansion direction as the wedge rod moves in the -Z direction. On the other hand, if the wedge rod moves in the +Z direction, the grindstone table and the grindstone 12 are moved in the contraction direction by the loading force of the loading member. In addition, as the loading member, an annular spring, an annular rubber, etc. can be used.

[0032] The rotating spindle 2 has a spline shaft portion 2b provided on the +Z direction side thereof supported on the bed 93 of the machine body 9 via a spline bearing 55, and is movable in the Z-axis direction relative to the spline bearing 55, and is rotatable around a central axis J1 along the length direction of the rotating spindle 2. Here, the rotating axis of the rotating spindle 2, i.e., the first rotating axis, coincides with the central axis J1.

[0033] The rotation drive unit 5 has a motor 51; pulleys 52 and 54; and a belt 53, which rotates the rotating main shaft 2 around its central axis J1, i.e., the first rotating axis. The spline shaft portion 2b of the rotating main shaft 2 is splined on the pulley 54. The pulley 54 is connected to the pulley 52 fixed to the motor shaft 51a of the motor 51 via the belt 53. The motor 51 is, for example, a servo motor having a position detection sensor and a torque sensor such as a rotary encoder built in, and the rotation amount of the motor 51 is detected by the position detection sensor. When the pulley 52 is rotated by the motor 51, the rotating main shaft 2 whose spline shaft portion 2b is splined with the pulley 54 and the honing tool 1 fixed to the rotating main shaft 2 are rotated.

[0034] The axial driving part 4 has a sliding body 42; a guide rail 43 for guiding the sliding body 42; a feed screw mechanism 41 for driving the sliding body 42; a coupler 45; and a motor 44, so that the rotating main shaft 2 moves in the direction along its central axis J1, i.e., the first rotating axis. The sliding body 42 supports the rotating main shaft 2 via a bearing (not shown) so that it can rotate. The guide rail 43 extends linearly along the Z-axis direction, and the sliding body 42 slides freely in the upward and downward directions on the guide rail 43. The feed screw mechanism 41 has a feed screw nut 41a to which the sliding body 42 is fixed; and a feed screw 41b arranged in the vertical direction, rotatably supported on the machine body 9 and threadedly matched with the feed screw nut 41a. The end of the feed screw 41b on the +Z direction side is connected to the motor shaft 44a of the motor 44 via the coupler 45. The motor 44 is a servomotor having a position detection sensor such as a rotary encoder built in, and the position detection sensor detects the rotation amount and phase of the motor 44. When the feed screw 41b is rotated by the motor 44, the feed screw nut 41a and the sliding body 42 to which the feed screw nut 41a is fixed move along the Z-axis direction, and the rotating spindle 2 and the honing tool 1 are raised and lowered.

[0035] The expansion drive unit 8 causes the grindstone 12 to expand and move via the expansion rod 87 and the wedge rod fixed to the expansion rod 87. The expansion drive unit 8 includes the expansion rod 87 to which the wedge rod is fixed; a rod drive mechanism 85; a spline shaft 86a; a gear mechanism 82; and a motor 81. The expansion rod can move along the Z-axis direction, and a wedge rod is connected to its end on the -Z direction side. The rod drive mechanism 85 is a mechanism for moving the expansion rod 87 in the vertical direction, and includes a driven body 85a connected to the expansion rod 87 and a feed screw 85b for moving the driven body 85a along the Z-axis direction. The feed screw 85b is rotatably supported on the sliding body 42 in a posture parallel to the rotating spindle 2. The expansion rod 87 is fixed to the driven body 85a, and it can move in the Z-axis direction relative to the rotating spindle 2 together with the expansion rod 87. The driven body 85a includes a feed screw nut (not shown) threadedly engaged with the feed screw 85b, and moves in the Z-axis direction along with the feed screw 85b when the feed screw 85b rotates around its central axis.

[0036] The spline shaft 86a has an end portion on the -Z direction side connected to the end portion on the +Z direction side of the feed screw 85b via a coupler 86c. In addition, the upper end portion of the spline shaft 86a is splined with the gear shaft 82a via a connecting member 86b, and can move relative to the gear shaft 82a in the Z-axis direction. In addition, the gear shaft 82a is meshed with a gear 82b fixed on the motor shaft 81a of the motor 81. The motor 81 is, for example, a servo motor having a position detection sensor and a torque sensor such as a rotary encoder built in, and the rotation amount of the motor 81 is detected by the position detection sensor. If the spline shaft 86a is rotated by the motor 81, the feed screw 85b connected thereto rotates, and the driven body 85a having a feed screw nut threadedly engaged with the feed screw 85b moves relative to the rotating spindle 2 in the Z-axis direction. Here, if the driven body 85a moves in the -Z direction, the expansion rod 87 and the wedge rod connected to the expansion rod 87 move in the -Z direction, and the grindstone 12 moves to expand. On the other hand, if the driven body 85a moves in the +Z direction, the expansion rod 87 and the wedge rod connected to the expansion rod 87 move in the +Z direction, and the grindstone 12 moves to contract by the above-mentioned loading member.

[0037] Workpiece holder 3, such as Figure 3 and Figure 4 As shown, the workpiece holder 3 has a holder body 34, a base portion 31 and a push member 32; the base portion 31 carries the workpiece W clamped by the holder body 34 together with the holder body 34; the push member 32 is plate-shaped, and a through window portion 32a is formed in the thickness direction, and is arranged in a state of abutting against the +Z direction side of the holder body 34 placed on the base portion 31. In addition, the workpiece holder 3 has a plurality of pillars 33, which are columnar, uprightly arranged on the periphery of the base portion 31, and fix the periphery of the push member 32 to the front end portion. The workpiece holder 3 holds the workpiece W in a posture in which the central axis J2 of its processing hole Wh is consistent with the central axis J1 of the rotating spindle 2.

[0038] The retainer body 34, such as Figure 5A and Figure 5BAs shown, there are a retaining tube 341, a retaining ring 342 and a base member 343. The retaining tube 341 is cylindrical and retains the workpiece W in a state where the workpiece W is embedded inside; the retaining ring 342 is annular and is embedded outside near the end of the retaining tube 341 on the +Z direction side; and the base member 343 supports the retaining tube 341 and the retaining ring 342 together so as to slide freely in the Y-axis direction. The base member 343 is fixed to the base portion 31. In addition, the retaining frame body 34 has two pins 3441 and two pins 3442. The two pins 3441 are respectively inserted into two through holes 341a, and the two through holes 341a are respectively opened at two locations facing each other in the X-axis direction near the end of the retaining tube 341 on the +Z direction side, sandwiching the center axis of the retaining tube 341. Here, a threaded hole 341b is provided on the retaining cylinder 341, which is connected to the through hole 341a from the end on the +Z direction side. The threaded hole 341b is a threaded hole for threading with a set screw 346, and the set screw 346 is used to prevent the pin 3441 from falling off from the through hole 341a when the front end is in contact with the pin 3441. Moreover, the pin 3441 is fixed to the inner side of the through hole 341a by the set screw 346. In addition, the front end of the pin 3441 is inserted into the through hole 342a that penetrates the side wall of the retaining ring 342, and the retaining cylinder 341 is guided by the pin 3411 inserted in the through hole 342a relative to the retaining ring 342, and is freely slidable in the X-axis direction.

[0039] In addition, two pins 3442 are respectively inserted into two through holes 342b, which are respectively provided at two locations in the peripheral wall of the retaining ring 342 and facing each other with the center of the retaining ring 342 sandwiched in the Y-axis direction. Here, a threaded hole (not shown) is also provided in the retaining ring 342, which is connected to the through hole 342b from the end on the +Z direction side thereof. The threaded hole is a threaded hole for threading with a set screw (not shown), which is used to prevent the pin 3442 from falling off from the through hole 342b when the front end is in contact with the pin 3442. In addition, the pin 3442 is fixed to the inner side of the through hole 342b by the set screw.

[0040] Furthermore, the holder body 34 has a workpiece rotation limiting portion 345, which has a protruding strip 345a, which is annular and protrudes on the +Z direction side. The workpiece rotation limiting portion 345 limits the rotation of the workpiece W around the central axis J1 of the rotation spindle 2 in a state where the protruding strip 345a is fitted into a recess Wtr at the end portion on the -Z direction side of the workpiece W. This workpiece rotation limiting portion 345 is placed on the +Z direction side of the base portion 31 and is slidable in the XY direction relative to the base portion 31. In addition, the retaining frame body 34 has a workpiece axial movement limiting portion 347, which is annular and has a protruding rib 347a that is partially embedded in the inner side of the window portion 32a of the pushing member 32, and the -Z direction side abuts against the end of the workpiece W on the +Z direction side, clamping the workpiece W together with the base member 3, limiting the relative movement of the workpiece W with respect to the workpiece retaining frame 3 in the direction of the center axis J2 of the processing hole Wh.

[0041] The base member 343 has a main body 343a and a support 343b. The main body 343a is flat and arranged on the -Z direction side of the workpiece W, and abuts against the end of the workpiece W on the +Z direction side. The support 343b extends from the main body 343a in the +Z direction, and a through hole 343c is provided at the front end. The through hole 343c is inserted through the front end of the pin 3442 fixed on the retaining ring 342. Moreover, the retaining ring 342 is guided by the pin 3442 inserted in the through hole 343c relative to the base member 343, and is free to slide in the Y-axis direction. Here, the retaining cylinder 341, the retaining ring 342, the pins 3441, 3442 and the base member 343 constitute a workpiece support mechanism that supports the workpiece W so that it can move in at least one of the X-axis direction and the Y-axis direction in a manner that the central axis J2 of the machining hole Wh of the workpiece W coincides with the rotation axis of the rotating spindle 2, that is, the central axis J1. In addition, the sliding mechanism is not limited to a structure for supporting the workpiece W so as to slide freely in the in-plane direction perpendicular to the center axis J1. For example, the sliding mechanism may be a workpiece supporting mechanism that supports the workpiece W in a state where the posture of the workpiece W can change in the in-plane direction perpendicular to the center axis J1 and in the direction in which the center axis J2 of the processed hole Wh is inclined relative to the center axis J1.

[0042] Return to Figure 3 and Figure 4The holder drive unit 6 moves the workpiece holder 3 in the direction opposite to the moving direction of the rotating spindle 2 by applying a driving force to the portion of the workpiece holder 3 corresponding to the extension line of the center axis J1 in the direction along the center axis J1. The holder drive unit 6 includes a rack 62 and a pinion 63. The rack 62 is a long rack, and its length direction is arranged along the direction of the center axis J1, that is, the Z axis; the pinion 63 rotates around the center axis J3 of the shaft 642 described later, which is orthogonal to the Z axis, that is, the second rotation axis, and meshes with the rack 62 on the extension line of the center axis J1 when viewed from the +X direction. In addition, the holder drive unit 6 includes a driving part body 69; a holder support body 61 that supports the workpiece holder 3; a gear drive part 64 that rotationally drives the pinion 63; and a track 65 that supports the holder support body 61 to be freely movable along the Z axis direction.

[0043] The holder support body 61 has a main piece 611 and a support piece 612. The main piece 611 is plate-shaped and is arranged in a posture that its thickness direction is orthogonal to the Z-axis direction. The support piece 612 is plate-shaped and is arranged in a manner that its thickness direction is along the Z-axis direction, and supports the workpiece holder 3 on the +Z direction side. A long hole 611a extending in the Z-axis direction and penetrating the main piece 611 in the thickness direction is formed in the main piece 611. In addition, the holder support body 61 has a sliding body (shown in the figure), which is fixed to the -Y direction side of the main piece 611 and can move freely in the Z-axis direction while being suspended on the rail 65.

[0044] The rack 62 has a plurality of teeth 62a arranged in parallel along the longitudinal direction, and is fixed to the main plate 611 in such a manner that the plurality of teeth 62a protrude toward the inner side of the long hole 611a when viewed from the +Y direction side. The pinion 63 has a wheel 631 that is circular when viewed from the top and a plurality of rollers 632 that are arranged at equal intervals along the circumferential direction of the wheel 631. The plurality of rollers 632 are supported on the wheel 631 so as to freely rotate around the respective central axes, with the central axes thereof being parallel to the central axis J3 of the shaft 642, i.e., the second rotation axis direction of the pinion 63. The pinion 63 is inserted into the long hole 611a of the retainer support body 61 in a state where the plurality of rollers 632 thereof are meshed with the teeth 62a of the rack 62.

[0045] The gear drive unit 64 includes a motor 641, a reducer 6, and a shaft 642. The reducer 6 includes an input shaft (not shown) connected to an output shaft (not shown) of the motor 641; the shaft 642 fixes a wheel 631 of a pinion 63 connected to an output shaft (not shown) of a reducer 643. The motor 641 is, for example, a servo motor having a position detection sensor such as a rotary encoder built in, and the position detection sensor detects the rotation amount and phase of the motor 641. The reducer 643 is, for example, a ball-type reducer.

[0046] In this cage drive unit 6, as shown in FIG. Fig. 6A As shown in FIG. 1 , if the pinion 63 fixing the gear driving unit 64 to the shaft 642 is rotated counterclockwise as shown by arrow AR11 when viewed from the +Y direction, the holder support body 61 fixing the rack 62 meshing with the pinion 63 moves toward the +Z direction as shown by arrow AR12. Figure 6B As shown in FIG. 1 , the holder support body 61 is arranged on the +Z direction side. On the other hand, if the holder support body 61 is arranged on the Figure 6B When the pinion 63 fixing the gear driving unit 64 to the shaft 642 is rotated clockwise as shown by arrow AR21 when viewed from the +Y direction, the rack support body 61 fixing the rack 62 meshing with the pinion 63 moves toward the -Z direction as shown by arrow AR22. Fig. 6A As shown, the holder support body 61 is arranged again on the -Z direction side. In this way, the gear driving unit 64 alternately and repeatedly rotates the pinion 63 in the counterclockwise direction and in the clockwise direction when viewed from the +Y direction, so that the holder support body 61 and the workpiece holder 3 supported on the holder support body 61 vibrate along the Z-axis direction.

[0047] Return to Figure 2 The control unit 10 is, for example, a PLC (Programable Logic Controller) having a CPU (Central Processing Unit) unit and an input / output control unit. Furthermore, the control unit 10 controls the actions of the gear drive unit 64, the rotation drive unit 5, the axial drive unit 4, and the expansion drive unit 8 of the holder drive unit 6 by outputting control signals to the gear drive unit 64, the rotation drive unit 5, the axial drive unit 4, and the expansion drive unit 8 of the holder drive unit 6 through the input / output control unit. The control unit 10 controls the axial drive unit 4 in such a manner that the rotating spindle 2 periodically vibrates along the Z-axis direction, and controls the gear drive unit 64 of the holder drive unit 6 in such a manner that the workpiece holder 3 periodically vibrates along the Z-axis direction according to the same period as the rotating spindle 2 and becomes a vibration waveform having a phase difference with the vibration waveform of the rotating spindle 2. The control unit 10, for example, controls the axial drive unit 4 to move the rotating spindle 2 in a first direction along the Z-axis direction, and controls the gear drive unit 64 to move the workpiece holder 3 in a second direction opposite to the above-mentioned first direction.

[0048] The control unit 10, for example, Fig. 7AAs shown, when the end of the rotating spindle 2 on the -Z direction side is arranged at position Pos11 and the end of the workpiece W on the +Z direction side is arranged at position Pos12, the axis direction driving unit 4 is controlled to move the rotating spindle 2 in the -Z direction as indicated by arrow AR13, and the gear driving unit 64 is controlled to move the workpiece holder 3 in the +Z direction as indicated by arrow AR12. Figure 7B As shown, the end of the rotating spindle 2 on the -Z direction side is arranged at position Pos21, and the end of the workpiece W held on the workpiece holder 3 on the +Z direction side is arranged at position Pos22, so that the rotating spindle 2 and the workpiece holder 3 are in a state of being close to each other. Figure 7B In the state shown in FIG. 1 , as shown by arrow AR23, the rotating spindle 2 is moved in the +Z direction, and the gear drive unit 64 is controlled to move the workpiece holder 3 in the -Z direction as shown by arrow AR22. Fig. 7A As shown, the end of the rotating spindle 2 on the -Z direction side is again arranged at the position Pos11, and the end of the workpiece W held on the workpiece holder 3 on the +Z direction side is arranged at the position Pos12, and the rotating spindle 2 and the workpiece holder 3 are separated from each other. In addition, the control unit 10 controls the axial direction driving unit 4 and the gear driving unit 64, and the rotating spindle 2 and the workpiece holder 3 are vibrated along the Z-axis direction by alternately and repeatedly moving the rotating spindle 2 in the -Z direction and the workpiece holder 3 in the +Z direction, and moving the rotating spindle 2 in the +Z direction and the workpiece holder 3 in the -Z direction.

[0049] In addition, the control unit 10, for example, Fig. 8A As shown, the axial direction drive unit 4 and the gear drive unit 64 are controlled in such a manner that the vibration waveform of the end portion on the -Z direction side of the rotating spindle 2 and the vibration waveform of the end portion on the +Z direction side of the workpiece W become sinusoidal waveforms of amplitudes L1 and L21, respectively. Here, the control unit 10 controls the gear drive unit 64 of the holder drive unit 6 in such a manner that the workpiece holder 3 is vibrated according to a vibration waveform having a phase difference of π radians with the vibration waveform of the rotating spindle 2. In addition, the control unit 10 controls the axial direction drive unit 4 and the gear drive unit 64 in such a manner that the relative speed of the workpiece W with respect to the rotating spindle 2 becomes 50 m / min, so that the moving speed of the rotating spindle 2 in the Z-axis direction becomes 25 m / min, and the moving speed of the workpiece W becomes 25 m / min.

[0050] Furthermore, the control unit 10 controls the gear driving unit 64 of the holder driving unit 6 in such a manner that the workpiece holder 3 vibrates so that the vibration amplitude becomes smaller as the weight of the workpiece W increases. Figure 8BAs shown in FIG. 1 , if the weight of the workpiece W increases, the gear drive unit 64 is controlled so that the amplitude of the vibration waveform at the end portion on the +Z direction side of the workpiece W changes from the amplitude L21 to the amplitude L22 which is smaller than the amplitude L21. In this case, the control unit 10 controls the axis direction drive unit 4 and the gear drive unit 64 so that the relative speed of the workpiece W to the rotating spindle 2 becomes 37.5 m / min, for example, so that the vibration period of the rotating spindle 2 and the vibration period of the workpiece W become equal, for example, so that the moving speed of the rotating spindle 2 in the Z-axis direction becomes 25 m / min and the moving speed of the workpiece W becomes 12.5 m / min.

[0051] Here, the features of the honing device according to the present embodiment will be described in comparison with the honing device according to the comparative example. Fig. 9 As shown in FIG. 1 , a holder driving unit 9006 is provided for driving the workpiece holder 3 in the Z-axis direction by a linear motor 9064. Fig. 9 In the embodiment, the same structure as in the embodiment is added with Figure 2 and Figure 4 The same symbols are used. The holder driving unit 9006 includes a holder support body 9061, a rail 9661, and a slide body 9662. The holder support body 9061 supports the workpiece holder 3. The rail 9661 is a long rail, and its length direction is arranged along the Z-axis direction. The slide body 9662 is free to move in the Z-axis direction in a state where the holder support body 9061 is fixed and suspended on the rail 9661. Here, the holder support body 9061 includes a main part 9611 and a support piece 612 fixed to the +Z direction side of the main part 9611. In addition, the linear motor 9064 includes a stator 9641, which is a long stator and is arranged along the rail 9661, and a rotor 9642. The rotor 9642 is moved in the Z-axis direction by a driving force in the direction of the central axis J94 along the length direction of the stator 9641.

[0052] In the holder drive unit 9006 of the comparative example, for example, when the workpiece W is honed, when the workpiece holder 3 is moved in the +Z direction, a driving force acts on the portion of the rotor 9642 corresponding to the stator 9641 in the direction indicated by the arrow AR91. In addition, when the honing tool 1 is moved in the -Z direction in a state where the honing tool 1 is inserted in the processing hole Wh, the grinding stone 12 of the honing tool 1 slides in the -Z direction on the inner wall of the processing hole Wh of the workpiece W held on the workpiece holder 3, and a resistance due to the friction between the grinding stone 12 and the inner wall of the processing hole Wh acts on the workpiece W in the direction indicated by the arrow AR92 along the central axis J2 of the processing hole Wh. In this way, in the honing device of the comparative example, the position where the driving force acts in the rotor 9642 and the position where the resistance acts on the workpiece W are offset in the direction orthogonal to the central axis J2 of the processing hole Wh. Therefore, a force in the direction of elastic deformation of the holder support body 9061 is applied to the holder support body 9061 as indicated by the arrow AR93 due to the inertial force associated with the dead weight of the workpiece holder 3 and the resistance force applied to the workpiece W. Furthermore, due to the elastic deformation of the holder support body 9061, the center axis J2 of the machining hole Wh of the workpiece W held by the workpiece holder 3 supported on the holder support body 9061 is inclined with respect to the Z-axis direction, and there is a risk that the machining accuracy of the machining hole Wh is reduced.

[0053] In contrast, in the honing apparatus according to the present embodiment, Figure 3 and Figure 4 As shown, the meshing portion of the rack 62 and the pinion 63 in the holder drive unit 6 is located near the center axis J2 of the machining hole Wh of the workpiece W held on the workpiece holder 3. Therefore, the holder drive unit 6 can act on the center axis J2 of the workpiece holder 3, that is, the portion corresponding to the extension line of the center axis J1 of the rotating spindle 2, in the direction along the center axis J1, J2. That is, during the honing process, the driving force acting on the workpiece holder 3, the inertial force accompanied by the dead weight of the workpiece holder 3, and the resistance force applied to the workpiece W can be made to act roughly on the center axes J1, J2. As a result, since the force in the direction of elastically deforming the holder support body 61 of the holder drive unit 6 is reduced, the center axis J2 of the workpiece W held by the workpiece holder 3 can be suppressed from tilting relative to the Z axis, and the machining accuracy of the machining hole Wh can be improved accordingly.

[0054] As described above, the axial direction driving unit 4 moves the rotating spindle 2 to which the honing tool 1 is fixed in the Z-axis direction. In addition, the holder driving unit 6 moves the workpiece holder 3 in the Z-axis direction by applying a driving force in the Z-axis direction to a portion of the workpiece holder 3 corresponding to the extension line of the center axis J1 of the rotating spindle 2. As a result, during the honing process of the workpiece W, the relative speed of the honing tool 1 with respect to the workpiece W can be increased while the position where the holder driving unit 6 applies the driving force to the workpiece holder W in the Z-axis direction of the rotating spindle 2 is made to roughly coincide with the position where the resistance due to the friction resistance between the processing hole Wh of the workpiece W held on the workpiece holder 3 and the grindstone 12 of the honing tool 1 acts. Therefore, since the occurrence of the force acting in the inclined direction of the workpiece holder 3 is suppressed, the inclination of the center axis J2 of the processing hole Wh of the workpiece W with respect to the Z-axis direction can be suppressed, and the processing accuracy of the workpiece W is improved.

[0055] In addition, the control unit 10 according to the present embodiment controls the holder drive unit 6 so as to vibrate the workpiece holder 3 according to a vibration waveform having a phase difference of π radians from the vibration waveform of the rotating spindle 2. As a result, the relative speed of the honing tool 1 with respect to the workpiece W during the honing process of the workpiece W can be maximized, and the processing efficiency can be improved accordingly.

[0056] However, when a linear motor or a feed screw nut is used to realize the holder drive unit, since the stator or feed screw of the linear motor is long, it is necessary to provide as much space as possible on the -Z direction side of the workpiece holder 3 to configure the entire holder drive unit. In particular, when a linear motor is used, if the rotor is to be driven at high speed, the stator is enlarged accordingly. In contrast, the holder drive unit 6 of the present embodiment includes the above-mentioned rack 62 and a pinion 63 meshing with the rack 62 on an extension line of the center axis J1 of the rotating spindle 2. Therefore, since the holder drive unit 6 is realized by components such as the rack 62 and the pinion 63 that are smaller than the stator or feed screw of the linear motor, the entire holder drive unit 6 can be miniaturized accordingly.

[0057] Furthermore, in the workpiece holder 3 of the present embodiment, the workpiece support mechanism supports the workpiece W so as to be movable in at least one of the X-axis direction and the Y-axis direction in such a manner that the center axis J2 of the machined hole Wh of the workpiece W coincides with the center axis J1 of the rotating spindle 2. Thus, when the workpiece holder 3 is vibrated, since the stress caused by the misalignment between the center axis J2 of the machined hole Wh of the workpiece W and the center axis J1 of the rotating spindle 2 can be suppressed from being applied to the workpiece W, the occurrence of a force in the direction in which the workpiece holder 3 as a whole is tilted can be suppressed.

[0058] The above is a description of the embodiment of the present invention, but the present invention is not limited to the structure of the above embodiment. For example, the following structure may be adopted: the control unit 10 controls the gear drive unit 64 of the holder drive unit 6 in such a way that the workpiece holder 3 vibrates according to a vibration waveform having a phase difference of less than π radians with the vibration waveform of the rotating spindle 2.

[0059] In the embodiment, the holder driving unit may also be a structure having a swing mechanism (not shown) and a swing reduction mechanism (not shown), wherein the swing mechanism supports the entire workpiece holder 3 on the +Z direction side of the support piece 612 of the holder support body 61 so that it can swing freely in a direction perpendicular to the Z axis direction, that is, in the direction along the XY plane; and the swing reduction mechanism reduces the swing of the workpiece holder 3. Here, as the swing reduction mechanism, for example, it may also have a slider (not shown) that abuts against the side of the workpiece holder 3 and moves freely in a direction perpendicular to the Z axis; a slider holding portion (not shown) that holds the slider so that it can move freely; and a loading portion (not shown) that loads the slider held by the slider holding portion in a direction close to the workpiece holder 3.

[0060] According to this configuration, the workpiece W can be adjusted so that the center axis J2 of the machined hole Wh of the workpiece W coincides with the center axis J1 of the rotation spindle 2 in the XY plane orthogonal to the Z-axis direction.

[0061] In the embodiment, an input unit (not shown) may also be provided, in which the user inputs amplitude ratio information indicating the amplitude ratio of the amplitude of the vibration waveform of the spindle to the amplitude of the vibration waveform of the workpiece holder. Here, as the input unit, for example, a touch pad, a keyboard input device, etc. may be cited. In this case, the control unit 10 only needs to control the axial direction drive unit 4 and the holder drive unit 6 in such a manner that the rotating spindle 2 and the workpiece holder 3 vibrate according to the amplitude ratio indicated by the amplitude ratio information input through the input unit.

[0062] According to this configuration, if the user inputs amplitude ratio information through the input unit, for example, in such a manner that the vibration amplitude of the rotating spindle 2 is constant and the vibration amplitude of the workpiece holder 3 is reduced as the weight of the workpiece W increases, the acceleration of the workpiece holder 3 when the workpiece holder 3 vibrates can be reduced accordingly when the weight of the workpiece W is large. Therefore, the load applied to the holder drive unit 6 when honing a heavy workpiece W can be reduced.

[0063] In the embodiment, an example in which the holder drive unit 6 is fixed to the base 92 is described. However, the present invention is not limited to this. Fig.10 and Fig.11As shown, the machine body 2009 may be provided, which is a long machine body, and is arranged with its length direction along the vertical direction, and the holder drive unit 6 is fixed to a support column 2091 that supports the bed 93 at the end portion on the vertical upper side. Fig.10 and Fig.11 In the embodiment, the same structure as in the embodiment is added with Figure 1 and Figure 2 Here, the holder drive unit 6 is fixed to the other end portion on the vertical lower side of the support column 2091. Here, the holder drive unit 6 is arranged in a posture where the central axis J3 of the shaft 642 to which the pinion 63 is fixed is along the X-axis direction.

[0064] According to this structure, since the bed 93 and the holder driving unit 6 can be collectively arranged near the support column 2091, the machine body 2009 can be reduced in size accordingly.

[0065] The above describes the embodiments and variations of the present invention, but the present invention can be made into various embodiments and variations without departing from the broad spirit and scope of the present invention. In addition, the above-mentioned embodiments are used to illustrate the embodiments of the present invention, not to limit the scope of the present invention. That is, the scope of the present invention is not represented by the embodiments but by the claims. Moreover, various variations implemented within the scope of the claims and the meaning of the invention equivalent thereto are deemed to be within the scope of the present invention.

[0066] This application is made based on Japanese Patent Application No. 2022-095448 filed on June 14, 2022. In this specification, the specification, claims and drawings of Japanese Patent Application No. 2022-095448 are incorporated by reference in their entirety.

[0067] Possibility of Industrial Application

[0068] The present invention is applicable to a honing device for machining gears, injector parts and the like used in a transmission.

[0069] Explanation of symbols

[0070] 1: Honing tool, 2: Rotating spindle, 2a: Lower end, 2b: Spline shaft, 3: Workpiece holder, 4: Axial drive unit, 5: Rotating drive unit, 6: Holder drive unit, 8: Extension drive unit, 9, 2009: Machine body, 10: Control unit, 11: Tool body, 12: Grinding stone, 31: Base, 32: Pushing member, 32a: Window, 33, 2091: Pillar, 34: Holder body, 41: Feed wire Lever mechanism, 41a: feed screw nut, 41b, 85b: feed screw, 42: sliding body, 43: guide rail, 45, 86c: coupler, 44, 51, 81, 641: motor, 44a, 51a: motor shaft, 52, 54: pulley, 53: belt, 55: spline bearing, 61: cage support, 62: rack, 62a: tooth, 63: pinion, 64: gear drive unit, 65: track, 69: Drive unit body, 82: gear mechanism, 82a: gear shaft, 82b: gear, 85: rod drive mechanism, 85a: driven body, 86a: spline shaft, 86b: connecting member, 87: extension rod, 91: support, 92: base, 93: bed, 341: retaining cylinder, 341a, 342a, 342b, 343c: through hole, 341b: threaded hole, 342: retaining ring, 343: base member, 343a: main Body, 343b: support portion, 345: workpiece rotation limiting portion, 345a: protrusion portion, 346: set screw, 347: workpiece axial movement limiting portion, 347a: rib, 611: main plate, 611a: long hole, 612: supporting plate, 631: wheel, 632: roller, 642: shaft, 643: reducer, 3441, 3442: pins, J1, J2, J3: center axis, W: workpiece, Wh: processing hole.

Claims

1. A honing device, wherein: Equipped with a honing tool, a spindle, a rotation drive unit, an axial drive unit, a workpiece holder and a holder drive unit. The honing tool is provided with a grinding stone at the front end; The spindle is a long spindle, and the honing tool is fixed in a state where the front end portion of the honing tool extends from one end side in the length direction; The rotation drive unit rotates the main shaft around a first rotation axis along the length direction of the main shaft; The axial direction driving unit moves the main axis in a first direction along the first rotation axis; The workpiece holder holds the workpiece in a state where the central axis of the machining hole of the workpiece is consistent with the first rotation axis; The holder driving unit moves the work holder in a second direction opposite to the first direction by applying a driving force in a direction along the first rotation axis to a portion of the work holder corresponding to an extension line of the first rotation axis.

2. The honing device according to claim 1, wherein: It also has a control unit. The control unit controls the axial direction driving unit in such a manner that the spindle vibrates periodically in the direction of the first rotating axis, and controls the holder driving unit in such a manner that the workpiece holder vibrates periodically in the direction of the first rotating axis with the same period as that of the spindle and becomes a vibration waveform having a phase difference with the vibration waveform of the spindle.

3. The honing device according to claim 2, wherein: The control unit controls the holder driving unit so as to vibrate the workpiece holder with a vibration waveform having a phase difference of π radians from a vibration waveform of the main shaft.

4. The honing device according to claim 2 or 3, wherein: The apparatus further comprises an input unit in which a user inputs amplitude ratio information indicating an amplitude ratio between an amplitude of the vibration waveform of the spindle and an amplitude of the vibration waveform of the workpiece holder, The control unit controls the axial direction driving unit and the holder driving unit so that the main shaft and the workpiece holder vibrate at an amplitude ratio indicated by the amplitude ratio information.

5. The honing device according to any one of claims 1 to 3, wherein: The cage drive unit has a rack and a pinion, The rack is a long rack, and is arranged in such a way that its length direction is along the first rotation axis; The pinion gear rotates around a second rotation axis orthogonal to the first rotation axis, and meshes with the rack on an extension line of the first rotation axis.

6. The honing device according to any one of claims 1 to 3, wherein: The workpiece holder has a workpiece rotation limiting portion, a workpiece axial movement limiting portion and a workpiece supporting mechanism. The workpiece rotation limiting portion limits the relative rotation of the workpiece relative to the workpiece holder around the central axis of the machining hole; The workpiece axial direction movement limiting portion limits the relative movement of the workpiece with respect to the workpiece holder in the central axis direction of the machining hole. The workpiece support mechanism is supported so as to be movable in a direction orthogonal to a direction along the first rotation axis so that a central axis of the machined hole coincides with the first rotation axis.

7. The honing device according to any one of claims 1 to 3, wherein: It also has a body, The machine body comprises a bed and a support column, wherein the bed collectively holds the honing tool, the spindle, the rotation drive unit and the axial drive unit; the support column is a long support column, which is arranged with its length direction along the vertical direction and supports the bed at one end portion on the vertical upper side. The holder driving unit is fixed to the other end portion on the vertical lower side of the support column.

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