WO2023243118A1

WO2023243118A1 - Honing device

Info

Publication number: WO2023243118A1
Application number: PCT/JP2022/043300
Authority: WO
Inventors: 真吾藤原; 智宏井上
Original assignee: 株式会社日進製作所
Priority date: 2022-06-14
Filing date: 2022-11-24
Publication date: 2023-12-21

Abstract

This honing device comprises: a honing tool (1); a rotary main shaft (2) to which the honing tool (1) is fixed; an axial-direction drive unit (4) that moves the rotary main shaft (2) in the Z-axis direction; a workpiece holder (3) that holds a workpiece (W) in a state in which a central axis (J2) of a work hole (Wh) of the workpiece (W) and a central axis (J1) of the rotary main shaft (2) coincide with each other; and a holder drive unit (6) that moves the workpiece holder (3) in the direction along the central axis (J1) by applying a driving force in the direction along the central axis (J1) to the portion of the workpiece holder (3) corresponding to the extended line of the central axis (J1) of the rotary main shaft (2).

Description

Honing equipment

The present invention relates to a honing device.

It is equipped with a spindle that is rotationally driven while holding a honing tool, and a work holder that holds a workpiece and is driven by a linear motor to vibrate vertically up and down, and drives the spindle to vibrate vertically. At the same time, a high-speed honing machine has been proposed that can reduce machining time by increasing the relative speed of the honing tool in the vertical direction with respect to the work by driving the work holder that holds the work so as to vibrate in the vertical direction. (For example, see Patent Document 1). In this high-speed honing machine, the long stator of the linear motor is arranged so that its longitudinal direction runs along the vertical direction, and the work holder fixed to the mover of the linear motor is arranged to the side of the stator. .

European Patent No. 2374574

However, in the high-speed honing machine described in Patent Document 1, when honing a workpiece, the position where the driving force acts from the stator to the mover in the direction orthogonal to the vertical direction and the workpiece held by the workholder The position where force is applied due to frictional resistance between the honing tool and the honing tool is misaligned. For this reason, especially when the force due to frictional resistance acts vertically downward, the gravitational force applied to the work holder is combined and forces the work holder fixed to the movable element in the direction of turning around the movable element as a fulcrum. This may cause the work holder to tilt with respect to the mover. In this case, the central axis of the machining hole of the workpiece may be inclined with respect to the vertical direction, and there is a possibility that the machining accuracy of the workpiece may be reduced.

The present invention has been made in view of the above reasons, and an object of the present invention is to provide a honing processing device that can improve the processing accuracy of a workpiece while shortening the processing time of the workpiece.

In order to achieve the above object, the honing device according to the present invention includes:
A honing tool with a grindstone at the tip,
a main shaft that is elongated and has the honing tool fixed thereto with a tip end of the honing tool extending from one end in the longitudinal direction;
a rotation drive unit that rotates the main shaft around a first rotation axis along the longitudinal direction of the main shaft;
an axial drive unit that moves the main shaft in a first direction along the first rotation axis;
a work holder that holds the work in a state where the central axis of the machined hole of the work and the first rotation axis are aligned;
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, the work holder is moved to a second direction opposite to the first direction. and a holder drive unit that moves the holder in the direction.

According to the present invention, the axial drive section moves the main shaft to which the honing tool is fixed in the first direction along the first rotation axis of the main shaft. In addition, the holder drive unit applies a driving force in a direction along the first rotation axis to a portion of the work holder that corresponds to an extension of the first rotation axis of the main shaft, thereby moving the work holder in the opposite direction to the first rotation axis. direction. As a result, the speed of the honing tool relative to the workpiece can be increased during honing of the workpiece, so that the machining time of the workpiece can be shortened. In addition, when honing a workpiece, in the direction along the first rotation axis of the spindle, the position where the holder drive unit applies the driving force to the workholder and the position between the workpiece held by the workholder and the honing tool are determined. It is possible to match the position where force due to frictional resistance acts. Therefore, the generation of force acting in the direction in which the work holder is tilted is suppressed, so that the central axis of the machined hole of the workpiece is suppressed from being tilted with respect to the first rotation axis direction, thereby improving the machining accuracy of the workpiece. Can be done.

1 is a perspective view of a honing device according to an embodiment of the present invention. FIG. 1 is a side view of a honing device according to an embodiment. It is a side view of a part of honing processing apparatus concerning an embodiment. 4 is a cross-sectional view taken along line AA in FIG. 3 of a part of the honing device according to the embodiment. FIG. It is a sectional view of the work holder concerning an embodiment. 5A is a cross-sectional view taken along line BB in FIG. 5A of the work holder according to the embodiment. FIG. It is a sectional view showing a state where a holder support body is arranged at a lower limit position about a holder drive unit concerning an embodiment. It is a sectional view showing a state where a holder support body is arranged at an upper limit position about a holder drive unit concerning an embodiment. FIG. 2 is a diagram showing a state in which the head is placed at the upper limit position during machining and the work holder is placed at the lower limit position during machining in the honing apparatus according to the embodiment. FIG. 3 is a diagram showing a state in which the head is placed at the lower limit position during machining and the work holder is placed at the upper limit position during machining in the honing apparatus according to the embodiment. FIG. 3 is a diagram showing vibration waveforms of the head and work holder of the honing device according to the embodiment. FIG. 3 is a diagram showing vibration waveforms of the head and work holder when the amplitude of the work holder of the honing device according to the embodiment is reduced. It is a side view of a part of honing processing apparatus concerning a comparative example. It is a perspective view of the honing processing device concerning a modification. FIG. 7 is a side view of a honing device according to a modification.

Hereinafter, a honing device according to an embodiment of the present invention will be described with reference to the drawings. The honing device according to the present embodiment includes a honing tool that is provided with a grindstone at its tip, and a honing tool that is long and fixed with the tip of the honing tool extending from one end in the longitudinal direction. The apparatus includes a main shaft, a rotation drive section that rotates the main shaft around a rotation axis along the longitudinal direction of the main shaft, and an axial drive section that moves the main shaft in a first direction along the rotation axis. In addition, this honing device has a work holder that holds the work in a state where the center axis of the workpiece hole and the rotation axis of the main spindle are aligned, and a part of the work holder that corresponds to the extension of the rotation axis. and a holder drive unit that moves the work holder in a second direction opposite to the first direction by applying a driving force in the direction along the direction.

As shown in FIG. 1, the honing device according to the present embodiment processes the inner wall of a hole in a workpiece, and includes a honing tool 1, a rotating main shaft 2, a work holder 3, and a work holder 3. It includes a holder drive unit 6 that supports and drives the work holder 3 so as to vibrate in the Z-axis direction, and a body 9. Hereinafter, in this specification, the vertical up-down direction will be expressed as ±Z direction or Z-axis direction, and the directions perpendicular to the vertical direction and mutually orthogonal will be expressed as ±X direction, ±Y direction or X-axis direction, and Y-axis direction, respectively. do. Further, as shown in FIG. 2, the honing device includes a rotational drive section 5, an axial drive section 4, an expansion drive section 8, a holder drive unit 6, a rotational drive section 5, an axial drive section 4, and an expansion drive section 8. A control section 10 that controls the operation of the drive section 8 is provided. In addition, in FIG. 2, the work W is arranged in such a posture that the center axis J2 of the processing hole Wh thereof and the center axis J1 of the rotating main shaft 2 coincide with each other. The body 9 includes a base 92 that supports the work holder 3 and the holder drive unit 6, and a head 93 that collectively holds the honing tool 1, the rotating main shaft 2, the rotation drive section 5, the axial drive section 4, and the expansion drive section 8. , a support 91 that stands on a base 92 and supports a head 93. The support column 91 is long and arranged with its longitudinal direction along the vertical direction, that is, the Z-axis direction, and supports the head 93 at its vertically upper end.

The honing tool 1 includes a tool main body 11 that has an elongated cylindrical shape and is replaceably attached to the rotating main shaft 2 so as to extend from the lower end 2a of the rotating main shaft 2 in the -Z direction, and It has a plurality of grindstones 12 that are provided at the side ends so as to be expandable and contractible in the radial direction of the tool body 11. Further, the honing tool 1 has a wedge portion (not shown) provided at the end on the -Z direction side, and the honing tool 1 has a wedge portion (not shown) provided at the end on the −Z direction side, and a grindstone of a grindstone stand (not shown) on which a grindstone 12 is fixed inside the tool body 11. A wedge rod (not shown) is arranged with the wedge portion in contact with an inclined surface on the opposite side to the tool body 12, and is used to expand and move the grindstone 12 by moving relative to the tool body 11 in the vertical direction. ) and a biasing member (not shown) that biases the grindstone 12 in the direction of contraction and movement. The wedge rod is connected to an expansion rod 87, which will be described later, which is arranged on the +Z direction side of the wedge rod inside the rotating main shaft 2. Further, the grindstone 12 is always urged in the contraction direction by the above-mentioned urging member. As a result, as the wedge rod moves in the −Z direction, the grindstone head and the grindstone 12 fixed to the whetstone head are pressed by the wedge portion and move in the expansion direction. On the other hand, when the wedge rod moves in the +Z direction, the grindstone head and the grindstone 12 move in the contraction direction due to the urging force of the urging member. Note that a ring spring, a ring-shaped rubber, or the like can be used as the biasing member.

The main rotating shaft 2 has a spline shaft portion 2b provided on the +Z direction side supported by the head 93 of the fuselage 9 via a spline bearing 55, and is movable in the Z-axis direction with respect to the spline bearing 55. It is rotatable around a central axis J1 along the longitudinal direction of the main body 2. Here, the rotation axis of the rotation main shaft 2, that is, the first rotation axis, coincides with the central axis J1.

The rotation drive unit 5 includes a motor 51, pulleys 52 and 54, and a belt 53, and rotates the rotation main shaft 2 around its central axis J1, that is, the first rotation axis. The spline shaft portion 2b of the rotating main shaft 2 is spline-fitted into the pulley 54. The pulley 54 is connected via a belt 53 to a pulley 52 fixed to a motor shaft 51a of the motor 51. The motor 51 is a servo motor with a built-in position detection sensor such as a rotary encoder and a torque sensor, and the amount of rotation 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 in which the spline shaft portion 2b is spline-fitted to the pulley 54 and the honing tool 1 fixed to the rotating main shaft 2 are rotated.

The axial drive unit 4 includes a slide body 42, a guide rail 43 that guides the slide body 42, a feed screw mechanism 41 that drives the slide body 42, a coupling 45, and a motor 44, and has a rotating main shaft. 2 in the direction along its central axis J1, that is, the first rotation axis. The slide body 42 rotatably supports the rotating main shaft 2 via a bearing (not shown). The guide rail 43 extends linearly along the Z-axis direction, and the slide body 42 can freely slide on the guide rail 43 in the vertical direction. The feed screw mechanism 41 includes a feed screw nut 41a to which a slide body 42 is fixed, and a feed screw 41b arranged along the vertical direction and rotatably supported by the body 9, and to which the feed screw nut 41a is screwed. , has. The end of the feed screw 41b on the +Z direction side is connected to the motor shaft 44a of the motor 44 via a coupling 45. The motor 44 is a servo motor with a built-in position detection sensor such as a rotary encoder, and the rotation amount and phase of the motor 44 are detected by the position detection sensor. When the feed screw 41b is rotated by the motor 44, the feed screw nut 41a and the slide body 42 to which the feed screw nut 41a is fixed move along the Z-axis direction, and the rotating main shaft 2 and the honing tool 1 move up and down.

The expansion drive unit 8 expands and moves the grindstone 12 via an expansion rod 87 and a wedge rod fixed to the expansion rod 87. The expansion drive unit 8 includes an expansion rod 87 to which a wedge rod is fixed, a rod drive mechanism 85, a spline shaft 86a, a gear mechanism 82, and a motor 81. The expansion rod is movable along the Z-axis direction, and has a wedge rod connected to its end on the -Z direction side. The rod drive mechanism 85 moves 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 by the slide body 42 in a position parallel to the rotation main shaft 2. An expansion rod 87 is fixed to the driven body 85a, and is movable together with the expansion rod 87 in the Z-axis direction relative to the rotation main shaft 2. The driven body 85a has a feed screw nut (not shown) screwed onto the feed screw 85b, and moves in the Z-axis direction when the feed screw 85b is rotated around its central axis.

The end of the spline shaft 86a on the −Z direction side is connected to the end of the feed screw 85b on the +Z direction via a coupling 86c. Further, the upper end portion of the spline shaft 86a is spline-fitted to the gear shaft 82a via a connecting member 86b, and is movable in the Z-axis direction with respect to the gear shaft 82a. Further, the gear shaft 82a meshes with a gear 82b fixed to a motor shaft 81a of the motor 81. The motor 81 is a servo motor with a built-in position detection sensor such as a rotary encoder and a torque sensor, and the amount of rotation of the motor 81 is detected by the position detection sensor. When the spline shaft 86a is rotated by the motor 81, the feed screw 85b connected thereto rotates, and the driven body 85a, which has a feed screw nut screwed onto the feed screw 85b, moves along the Z-axis relative to the rotation main shaft 2. move in the direction. Here, when 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 expands. On the other hand, when 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 accordingly, the grindstone 12 is contracted and moved by the aforementioned biasing member.

As shown in FIGS. 3 and 4, the work holder 3 includes a holder body 34, a base portion 31 on which the work W held by the holder body 34 is placed together with the holder body 34, and is plate-shaped and has a thickness. A holding member 32 is provided in which a window portion 32a penetrating in the direction is formed and is disposed in contact with the +Z direction side of the holder main body 34 placed on the base portion 31. Further, the work holder 3 has a plurality of pillars 33 which are columnar and are erected around the periphery of the base portion 31 and to which the periphery of the presser member 32 is fixed to the tip end. The work holder 3 holds the work W in a posture in which the center axis J2 of the machined hole Wh coincides with the center axis J1 of the rotating main shaft 2.

As shown in FIGS. 5A and 5B, the holder main body 34 includes a cylindrical holding cylinder 341 that holds the workpiece W with the workpiece W fitted therein, and an annular holding cylinder 341 on the +Z direction side of the holding cylinder 341. It has a retaining ring 342 that is externally fitted near the end, and a base member 343 that collectively supports the retaining cylinder 341 and the retaining ring 342 so as to be slidable in the Y-axis direction. The base member 343 is fixed to the base portion 31. Further, the holder main body 34 has two pins 3441 and two pins 3442. The two pins 3441 are inserted into two through-holes 341a formed at two locations facing each other across the central axis of the holding cylinder 341 in the X-axis direction near the end of the holding cylinder 341 on the +Z direction side. has been done. Here, the holding cylinder 341 has a resistor that communicates with the through hole 341a from the end on the +Z direction side and prevents the pin 3441 from falling off from the through hole 341a when the tip is in contact with the pin 3441. A screw hole 341b into which a screw 346 is screwed is provided. The pin 3441 is fixed inside the through hole 341a by a set screw 346. The tip of the pin 3441 is inserted into a through hole 342a that passes through the side wall of the retaining ring 342, and the retaining cylinder 341 is guided by the pin 3411 inserted into the through hole 342a with respect to the retaining ring 342. It is slidable in the X-axis direction.

Further, the two pins 3442 are respectively inserted into two through holes 342b bored at two locations facing each other across the center of the retaining ring 342 in the Y-axis direction on the peripheral wall of the retaining ring 342. Here, the retaining ring 342 also has a resistor that communicates with the through hole 342b from the end on the +Z direction side and prevents the pin 3442 from falling off from the through hole 342b when the tip is in contact with the pin 3442. A screw hole (not shown) into which a screw (not shown) is screwed is provided. The pin 3442 is fixed inside the through hole 342b with a set screw.

Furthermore, the holder main body 34 has an annular protrusion 345a that protrudes in the +Z direction, and the protrusion 345a is fitted into a recess Wtr provided at the -Z direction end of the workpiece W. It has a workpiece rotation regulating part 345 that regulates the rotation of the workpiece W around the central axis J1 of the rotating main shaft 2 in this state. The workpiece rotation regulating section 345 is placed on the +Z direction side of the base section 31 and is slidable relative to the base section 31 in the X and Y directions. The holder main body 34 is annular and has a protruding rib 347a that is partially fitted inside the window 32a of the holding member 32, and the -Z direction side is connected to the +Z direction end of the workpiece W. It has a workpiece axial movement restriction part 347 that comes into contact with the base member 343 and clamps the workpiece W to restrict movement of the workpiece W relative to the workpiece holder 3 in the direction of the center axis J2 of the processing hole Wh.

The base member 343 has a flat shape, and includes a main body 343a that is arranged on the −Z direction side of the work W and abuts the +Z direction end of the work W, and a main body 343a that extends from the main body 343a in the +Z direction and has a tip end. It has a support portion 343b provided with a through hole 343c through which the tip of a pin 3442 fixed to the retaining ring 342 is inserted. The retaining ring 342 is slidable in the Y-axis direction with respect to the base member 343 while being guided by a pin 3442 inserted through the through hole 343c. Here, from the holding cylinder 341, the holding ring 342, the pins 3441, 3442, and the base member 343, the center axis J2 of the machined hole Wh of the workpiece W is aligned with the rotation axis of the rotating main shaft 2, that is, the center axis J1. , a workpiece support mechanism is configured to support the workpiece W so as to be movable in at least one of the X-axis direction and the Y-axis direction. Note that the sliding mechanism is not limited to one for slidably supporting the workpiece W in the in-plane direction orthogonal to the central axis J1. For example, the sliding mechanism moves the workpiece W in a state in which the posture of the workpiece W is variable in an in-plane direction perpendicular to the central axis J1 and in a direction in which the central axis J2 of the machined hole Wh is inclined with respect to the central axis J1. It may also be a workpiece support mechanism that supports.

Returning to FIGS. 3 and 4, the holder drive unit 6 drives the work holder 3 by applying a driving force in the direction along the central axis J1 to a portion of the work holder 3 corresponding to the extension line of the central axis J1. The rotating main shaft 2 is moved in the opposite direction to the moving direction. The holder drive unit 6 includes a rack gear 62 which is elongated and whose longitudinal direction is arranged along the central axis J1 direction, that is, along the Z axis, and a central axis J3 of a shaft 642, which will be described later, which is orthogonal to the Z axis. A pinion gear 63 that rotates around two rotational axes and meshes with the rack gear 62 on an extension line of the center axis J1 when viewed from the +X direction is provided. The holder drive unit 6 also includes a drive main body 69, a holder support 61 that supports the work holder 3, a gear drive unit 64 that rotationally drives the pinion gear 63, and a drive unit 69 that rotates the holder support 61 along the Z-axis direction. A rail 65 for movably supporting.

The holder support 61 includes a main piece 611 which is plate-shaped and arranged so that its thickness direction is perpendicular to the Z-axis direction, and a main piece 611 which is plate-shaped and arranged so that its thickness direction is perpendicular to the Z-axis direction, and which has a +Z axis. It has a support piece 612 that supports the work holder 3 on the direction side. The main piece 611 is formed with a long hole 611a that extends in the Z-axis direction and passes through the main piece 611 in the thickness direction. Further, the holder support 61 has a sliding body (shown) that is fixed to the -Y direction side of the main piece 611 and is movable in the Z-axis direction while being suspended from the rail 65.

The rack gear 62 has a plurality of teeth 62a arranged in parallel along the longitudinal direction, and is fixed to the main piece 611 so that the plurality of teeth 62a protrude inside the elongated hole 611a when viewed from the +Y direction side. . The pinion gear 63 includes a wheel 631 that is circular in plan view, and a plurality of rollers 632 arranged around the wheel 631 at equal intervals along the circumferential direction. Each of the plurality of rollers 632 has a central axis parallel to the central axis J3 of the shaft 642, that is, the second rotation axis direction of the pinion gear 63, and is supported by the wheel 631 so as to be rotatable around each central axis. The pinion gear 63 is inserted into the elongated hole 611a of the holder support 61 with the plurality of rollers 632 meshing with the teeth 62a of the rack gear 62.

The gear drive unit 64 includes a motor 641, a reducer 643 having an input shaft (not shown) connected to the output shaft (not shown) of the motor 641, and a reducer 643 having an input shaft (not shown) connected to the output shaft (not shown) of the motor 641. A shaft 642 is connected to the shaft 642 and a wheel 631 of a pinion gear 63 is fixed thereto. The motor 641 is, for example, a servo motor with a built-in position detection sensor such as a rotary encoder, and the rotation amount and phase of the motor 641 are detected by the position detection sensor. The speed reducer 643 is, for example, a ball speed reducer.

In this holder drive unit 6, as shown in FIG. 6A, when the gear drive section 64 rotates the pinion gear 63 fixed to the shaft 642 counterclockwise when viewed from the +Y direction as shown by the arrow AR11, the pinion gear 63 The holder support 61 to which the rack gear 62 that meshes with is fixed moves in the +Z direction as shown by arrow AR12. Then, as shown in FIG. 6B, the holder support body 61 is arranged on the +Z direction side. On the other hand, with the holder support 61 disposed at the position shown in FIG. 6B, the gear drive unit 64 rotates the pinion gear 63 fixed to the shaft 642 clockwise when viewed from the +Y direction as shown by the arrow AR21. Then, the holder support 61 to which the rack gear 62 meshing with the pinion gear 63 is fixed moves in the -Z direction as shown by arrow AR22. Then, as shown in FIG. 6A, the holder support body 61 is placed again on the −Z direction side. In this way, the gear drive unit 64 alternately rotates the pinion gear 63 counterclockwise and clockwise when viewed from the +Y direction, thereby moving the holder support 61 and the work holder supported by the holder support 61. 3 is vibrated along the Z-axis direction.

Returning to FIG. 2, the control unit 10 is, for example, a PLC (Programmable Logic Controller), and includes a CPU (Central Processing Unit) unit and an input/output control unit. The control section 10 controls these operations by outputting control signals to the gear drive section 64, rotation drive section 5, axial drive section 4, and expansion drive section 8 of the holder drive unit 6 via the input/output control unit. control. The control unit 10 controls the axial drive unit 4 so that the rotation main shaft 2 periodically vibrates along the Z-axis direction, and the work holder 3 periodically vibrates along the Z-axis direction at the same period as the rotation main shaft 2. The gear drive section 64 of the holder drive unit 6 is controlled so that the vibration waveform vibrates symmetrically and has a phase difference with the vibration waveform of the rotating main shaft 2. The control unit 10 controls, for example, the axial drive unit 4 to move the rotating main shaft 2 in the first direction along the Z-axis direction, and also controls the gear drive unit 64 to move the work holder 3 in the above-mentioned first direction. The object is moved in a second direction opposite to the first direction.

For example, as shown in FIG. 7A, the control unit 10 controls the rotational speed in the axial direction in a state in which the -Z direction side end of the rotating main shaft 2 is placed at position Pos11 and the +Z direction side end of the workpiece W is placed at position Pos12. The drive section 4 is controlled to move the rotating main shaft 2 in the -Z direction as shown by the arrow AR13, and the gear drive section 64 is controlled to move the work holder 3 in the +Z direction as shown by the arrow AR12. Move to. As a result, as shown in FIG. 7B, the -Z direction side end of the rotating main shaft 2 is placed at position Pos21, and the +Z direction side end of the workpiece W held by the work holder 3 is placed at position Pos22. The rotating main shaft 2 and the work holder 3 are brought into close proximity to each other. Then, in the state shown in FIG. 7B, the control unit 10 moves the rotation main shaft 2 in the +Z direction as shown by the arrow AR23, and controls the gear drive unit 64 to move the work holder as shown by the arrow AR22. 3 in the -Z direction. As a result, as shown in FIG. 7A, the end of the rotating main shaft 2 on the -Z direction side is placed at position Pos11, and the end of the workpiece W held by the work holder 3 on the +Z direction is placed at position Pos12. , the rotating main shaft 2 and the work holder 3 are in a state separated from each other. Then, the control unit 10 controls the axial drive unit 4 and the gear drive unit 64 to move the main rotation shaft 2 in the -Z direction, move the work holder 3 in the +Z direction, and move the main rotation shaft 2 in the +Z direction. By alternately repeating the movement in the direction and the movement of the work holder 3 in the -Z direction, the rotation main shaft 2 and the work holder 3 are vibrated along the Z-axis direction.

Further, as shown in FIG. 8A, for example, the control unit 10 controls the vibration waveform at the end of the rotating main shaft 2 in the -Z direction and the vibration waveform at the end of the workpiece W in the +Z direction to have an amplitude L1, respectively. The axial drive section 4 and the gear drive section 64 are controlled so as to have a sinusoidal waveform of L21. Here, the control section 10 controls the gear drive section 64 of the holder drive unit 6 to vibrate the work holder 3 with a vibration waveform having a phase difference of π radians from the vibration waveform of the rotation main shaft 2. Further, the control unit 10 controls the relative speed of the workpiece W with respect to the rotational main shaft 2 such that, for example, the moving speed of the rotating main shaft 2 in the Z-axis direction is 25 m/min, and the moving speed of the workpiece W is 25 m/min. The axial drive section 4 and the gear drive section 64 are controlled so that the speed becomes 50 m/min.

Furthermore, the control unit 10 controls the gear drive unit 64 of the holder drive unit 6 to vibrate the work holder 3 so that the vibration amplitude becomes smaller as the weight of the work W increases. For example, as shown in FIG. 8B, when the weight of the workpiece W increases, the control unit 10 changes the amplitude of the vibration waveform at the end of the workpiece W in the +Z direction from the amplitude L21 to the amplitude L22, which is smaller than the amplitude L21. The gear drive section 64 is controlled to change the amount. In this case, the control unit 10 sets, for example, the moving speed of the rotating main shaft 2 in the Z-axis direction to 25 m/min, and the moving speed of the workpiece W so that the vibration period of the rotating main shaft 2 and the vibration period of the work W are equal to each other. is 12.5 m/min, and the axial drive section 4 and gear drive section 64 are controlled so that the relative speed of the workpiece W to the rotating main shaft 2 is 37.5 m/min.

Here, the features of the honing device according to the present embodiment will be explained while comparing with a honing device according to a comparative example. The honing device according to the comparative example includes a holder drive unit 9006 that drives the work holder 3 in the Z-axis direction by a linear motor 9064 as shown in FIG. Note that in FIG. 9, the same components as in the embodiment are given the same reference numerals as in FIGS. 2 and 4. The holder drive unit 9006 includes a holder support 9061 that supports the work holder 3, a long rail 9661 arranged in such a manner that its longitudinal direction is along the Z-axis direction, and a holder support 9061 fixed to the rail 9661. It has a slide body 9662 that is movable in the Z-axis direction in a suspended state. Here, the holder support body 9061 has a main part 9611 and a support piece 612 fixed to the +Z direction side of the main part 9611. The linear motor 9064 also includes a long stator 9641 arranged along the rail 9661, and a movable element that moves in the Z-axis direction by a driving force in the direction of the central axis J94 along the longitudinal direction of the stator 9641. 9642.

In the holder drive unit 9006 according to the comparative example, when moving the work holder 3 in the +Z direction during honing of the work W, for example, a driving force is applied to the portion of the movable element 9642 corresponding to the stator 9641 in the direction indicated by the arrow AR91. acts. Further, when moving the honing tool 1 in the -Z direction with the honing tool 1 inserted into the processing hole Wh, the grindstone 12 of the honing tool 1 touches the inner wall of the processing hole Wh of the work W held by the work holder 3. - Along with sliding in the Z direction, a resistance force due to friction between the grindstone 12 and the inner wall of the processing hole Wh is applied to the workpiece W in the direction shown by the arrow AR92 along the central axis J2 of the processing hole Wh. act. In this way, in the honing device according to the comparative example, the position where the driving force acts on the mover 9642 and the position where the resistance force applied to the workpiece W acts are misaligned in the direction perpendicular to the central axis J2 of the processed hole Wh. ing. Therefore, a force acts on the holder support 9061 in a direction to elastically deform the holder support 9061 due to an inertial force due to the weight of the work holder 3 and a resistance force applied to the work W, as shown by an arrow AR93. Then, due to the elastic deformation of the holder support 9061, the central axis J2 of the machining hole Wh of the workpiece W held by the work holder 3 supported by the holder support 9061 is inclined with respect to the Z-axis direction, and the machining hole There is a possibility that the machining accuracy of Wh may decrease.

On the other hand, in the honing device according to the present embodiment, as shown in FIGS. 3 and 4, the portion of the holder drive unit 6 where the rack gear 62 and the pinion gear 63 mesh with each other is held by the work holder 3. It is located near the center axis J2 of the machined hole Wh of the workpiece W. Therefore, the holder drive unit 6 applies a driving force to the central axis J2 of the work holder 3, that is, to the portion corresponding to the extension of the central axis J1 of the rotating main shaft 2 in the direction along the central axes J1 and J2. Can be done. In other words, during honing, the driving force acting on the work holder 3, the inertia force due to the weight of the work holder 3, and the resistance force applied to the work W can be made to act approximately on the central axes J1 and J2. can. This reduces the force in the direction of elastically deforming the holder support 61 of the holder drive unit 6, thereby preventing the central axis J2 of the work W held by the work holder 3 from being inclined with respect to the Z-axis. This can be suppressed, and the machining accuracy of the machined hole Wh can be increased accordingly.

As explained above, the axial drive unit 4 moves the rotating main shaft 2 to which the honing tool 1 is fixed in the Z-axis direction. The holder drive unit 6 also moves the work holder 3 in the Z-axis direction by applying a driving force in the Z-axis direction to a portion of the work holder 3 that corresponds to an extension of the central axis J1 of the rotating main shaft 2. As a result, when honing the workpiece W, the holder drive unit 6 applies a driving force to the workpiece holder W in the Z-axis direction of the rotating main shaft 2 while increasing the speed of the honing tool 1 relative to the workpiece W. The position can be made substantially coincident with the position where the resistance force due to the frictional resistance between the machining hole Wh of the work W held by the work holder 3 and the grindstone 12 of the honing tool 1 acts. Therefore, the generation of a force acting in the direction in which the work holder 3 is tilted is suppressed, so that the center axis J2 of the machined hole Wh of the work W is suppressed from being tilted with respect to the Z-axis direction, and the machining accuracy of the work W is improved. can be improved.

Furthermore, the control unit 10 according to the present embodiment controls the holder drive unit 6 to vibrate the work holder 3 with a vibration waveform that has a phase difference of π radians from the vibration waveform of the rotation main shaft 2. Thereby, the speed of the honing tool 1 relative to the workpiece W during honing of the workpiece W can be maximized, so that the machining efficiency can be increased accordingly.

By the way, when attempting to realize the holder drive unit using a linear motor or a feed screw nut, the entire holder drive unit must be mounted on the −Z direction side of the work holder 3 because the stator or feed screw of the linear motor is long. It is necessary to provide as much space as possible. In particular, when a linear motor is used, if the movable element is driven at high speed, the stator becomes larger. On the other hand, the holder drive unit 6 according to the present embodiment includes the above-described rack gear 62 and a pinion gear 63 that meshes with the rack gear 62 on an extension line of the central axis J1 of the rotation main shaft 2. As a result, the holder drive unit 6 is realized with smaller parts compared to the stator or feed screw of a linear motor such as the rack gear 62 and pinion gear 63, so the overall size of the holder drive unit 6 can be reduced accordingly. can be achieved.

Furthermore, in the work holder 3 according to the present embodiment, the work support mechanism moves the work W in the X-axis direction so that the center axis J2 of the machined hole Wh of the work W and the center axis J1 of the rotating main shaft 2 coincide with each other. It is supported so as to be movable in at least one of the Y-axis direction. Thereby, when the work holder 3 is vibrated, distortion caused by the misalignment between the center axis J2 of the machined hole Wh of the work W and the center axis J1 of the rotating main shaft 2 is suppressed from being applied to the work W. Therefore, the generation of force in the direction in which the entire work holder 3 is tilted can be suppressed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations of the above-described embodiments. For example, the control section 10 controls the gear drive section 64 of the holder drive unit 6 to vibrate the work holder 3 with a vibration waveform that has a phase difference of less than π radian with the vibration waveform of the rotation main shaft 2. It's okay.

In the embodiment, the holder drive unit can swing the entire work holder 3 in a direction perpendicular to the Z-axis direction, that is, in a direction along the XY plane, on the +Z direction side of the support piece 612 of the holder support body 61. It may have a swing mechanism (not shown) for supporting the work holder 3 and a swing reduction mechanism (not shown) for reducing the swing of the work holder 3 . Here, the swing reduction mechanism includes, for example, a slider (not shown) that abuts the side of the work holder 3 and is movable in a direction perpendicular to the Z-axis, and a slider holding section (not shown) that movably holds the slider. (not shown) and an urging section (not shown) that urges the slider held by the slider holding section in a direction toward the work holder 3.

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 rotating main shaft 2 in the XY plane orthogonal to the Z-axis direction.

The embodiment may include an input unit (not shown) through which a user inputs amplitude ratio information indicating an amplitude ratio between the amplitude of the vibration waveform of the main shaft and the amplitude of the vibration waveform of the work holder. good. Here, examples of the input unit include a touch pad, a key input device, and the like. In this case, the control unit 10 controls the axial drive unit 4 and the holder drive unit 6 so that the rotating main shaft 2 and the work holder 3 vibrate at the amplitude ratio indicated by the amplitude ratio information input via the input unit. do it.

According to this configuration, if the user inputs the amplitude ratio information via the input unit such that the vibration amplitude of the rotating main shaft 2 is kept constant and the vibration amplitude of the work holder 3 becomes smaller as the weight of the work W increases, for example. When the weight of the work W is large, the acceleration of the work holder 3 when vibrating the work holder 3 can be reduced accordingly. Therefore, the load applied to the holder drive unit 6 when honing a heavy workpiece W can be reduced.

In the embodiment, an example in which the holder drive unit 6 is fixed to the base 92 has been described. However, the present invention is not limited to this, and as shown in FIGS. 10 and 11, the holder is elongated and is arranged with its longitudinal direction along the vertical direction, and is attached to a support 2091 that supports the head 93 at the vertically upper end. It may also include a body 2009 to which the drive unit 6 is fixed. Note that in FIGS. 10 and 11, the same components as in the embodiment are denoted by the same reference numerals as in FIGS. 1 and 2. Here, the holder drive unit 6 is fixed to the other end of the column 2091 on the vertically lower side. Here, the holder drive unit 6 is arranged with the center axis J3 of the shaft 642 to which the pinion gear 63 is fixed aligned along the X-axis direction.

According to this configuration, since the head 93 and the holder drive unit 6 can be arranged together near the support column 2091, the size of the body 2009 can be reduced accordingly.

Although the embodiments and modifications of the present invention have been described above, various embodiments and modifications can be made to the present invention without departing from the broad spirit and scope of the invention. Further, the embodiments described above are for explaining the present invention, and do not limit the scope of the present invention. That is, the scope of the present invention is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the meaning of the invention equivalent thereto are considered to be within the scope of this invention.

This application is based on Japanese Patent Application No. 2022-095448 filed on June 14, 2022. The entire specification, claims, and drawings of Japanese Patent Application No. 2022-095448 are incorporated herein by reference.

The present invention is suitable for a honing device that processes gears, injector parts, etc. used in transmissions.

1: Honing tool, 2: Rotating main shaft, 2a: Lower end, 2b: Spline shaft section, 3: Work holder, 4: Axial drive section, 5: Rotation drive section, 6: Holder drive unit, 8: Expansion drive section , 9, 2009: Machine body, 10: Control section, 11: Tool body, 12: Grindstone, 31: Base section, 32: Holding member, 32a: Window section, 33, 2091: Support column, 34: Holder main body, 41: Feed screw mechanism, 41a: Feed screw nut, 41b, 85b: Feed screw, 42: Slide body, 43: Guide rail, 45, 86c: Coupling, 44, 51, 81, 641: Motor, 44a, 51a: Motor shaft , 52, 54: Pulley, 53: Belt, 55: Spline bearing, 61: Holder support, 62: Rack gear, 62a: Teeth, 63: Pinion gear, 64: Gear drive section, 65: Rail, 69: Drive section main body , 82: gear mechanism, 82a: gear shaft, 82b: gear, 85: rod drive mechanism, 85a: driven body, 86a: spline shaft, 86b: connecting member, 87: expansion rod, 91: strut, 92: base, 93 : Head, 341: Holding cylinder, 341a, 342a, 342b, 343c: Through hole, 341b: Screw hole, 342: Holding ring, 343: Base member, 343a: Main body, 343b: Support column, 345: Work rotation regulating section , 345a: protrusion, 346: potato screw, 347: workpiece axial movement restriction section, 347a: rib, 611: main piece, 611a: long hole, 612: support piece, 631: wheel, 632: roller, 642: Shaft, 643: Reducer, 3441, 3442: Pin, J1, J2, J3: Central axis, W: Workpiece, Wh: Machining hole

Claims

A honing tool with a grindstone at the tip,
a main shaft that is elongated and has the honing tool fixed thereto with a tip end of the honing tool extending from one end in the longitudinal direction;
a rotation drive unit that rotates the main shaft around a first rotation axis along the longitudinal direction of the main shaft;
an axial drive unit that moves the main shaft in a first direction along the first rotation axis;
a work holder that holds the work in a state where the central axis of the machined hole of the work and the first rotation axis are aligned;
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, the work holder is moved to a second direction opposite to the first direction. a holder drive unit that moves the holder in the direction;
Honing processing equipment.
The axial drive unit is controlled so that the main shaft vibrates periodically in a direction along the first rotation axis, and the work holder vibrates at the same period as the main shaft in a direction along the first rotation axis. further comprising a control unit that controls the holder drive unit so that the vibration waveform vibrates periodically and has a phase difference with the vibration waveform of the main shaft;
The honing device according to claim 1.
The control unit controls the holder drive unit to vibrate the work holder with a vibration waveform that has a phase difference of π radians from the vibration waveform of the main shaft.
The honing device according to claim 2.
further comprising an input section through which a user inputs amplitude ratio information indicating an amplitude ratio between the amplitude of the vibration waveform of the main shaft and the amplitude of the vibration waveform of the work holder,
The control unit controls the axial drive unit and the holder drive unit so that the main shaft and the work holder vibrate at an amplitude ratio indicated by the amplitude ratio information.
The honing device according to claim 2 or 3.
The holder drive unit includes:
a rack gear that is long and arranged so that its longitudinal direction is along the first rotation axis;
a pinion gear that rotates around a second rotation axis perpendicular to the first rotation axis and meshes with the rack gear on an extension of the first rotation axis;
The honing device according to any one of claims 1 to 3.
The work holder is
a workpiece rotation regulating part that regulates rotation of the workpiece relative to the workpiece holder around a central axis of the machined hole;
a workpiece axial movement restriction portion that restricts movement of the workpiece relative to the workpiece holder in the direction of the center axis of the machined hole;
a workpiece support mechanism that supports the workpiece so that it is movable in a direction perpendicular to a direction along the first rotational axis so that the central axis of the processed hole coincides with the first rotational axis;
The honing device according to any one of claims 1 to 3.
a head that collectively holds the honing tool, the main shaft, the rotary drive section, and the axial drive section; further comprising a body having a support for supporting the head;
The holder drive unit is fixed to the other vertically lower end of the support column.
The honing device according to any one of claims 1 to 3.