CN1810446B

CN1810446B - Method and device for grinding

Info

Publication number: CN1810446B
Application number: CN 200610003207
Authority: CN
Inventors: 西口正巳; 平冈贵树
Original assignee: Koyo Machine Industries Co Ltd
Current assignee: JTEKT Machine Systems Corp
Priority date: 2005-01-28
Filing date: 2006-01-27
Publication date: 2010-06-23
Anticipated expiration: 2026-01-27
Also published as: JP4486898B2; CN1810446A; JP2006205304A

Abstract

The present invention provides a grinding method capable of preventing abrasion of only a part of a grinding action surface of a cup-shaped grinding wheel, by changing a contact position of the cup-shaped grinding wheel and a work. The cup-shaped grinding wheel T having the annular grinding action surface and the cylindrical work W are respectively arranged so that these axes are mutually orthogonal, and the cup-shaped grinding wheel T and the work W are rotated around the axis. An outer peripheral surface of the work W is ground by contacting the grinding action surface with the outer peripheral surface of the work W. Every time when rotating the work W by a preset frequency in a state of contacting the grinding action surface of the cup-shaped grinding wheel T with the outer peripheral surface of the work W, the cup-shaped grinding wheel T and the work W are relatively moved in the direction orthogonal to both the axis of the cup-shaped grinding wheel T and the axis of the work W, to change a position for contacting the grinding action surface with the outer peripheral surface of the work W.

Description

Grinding method and grinding device

Technical Field

The present invention relates to a grinding method and a grinding apparatus for grinding an outer peripheral surface of a workpiece which is processed into a cylindrical shape by using a grinding action surface of a cup-shaped grinding wheel having an annular grinding action surface.

Background

As an example of the cylindrical workpiece, for example, as shown in fig. 13, a piston W which includes a vane (protrusion) Wa formed on an outer peripheral surface and a through hole Wb opened at both end surfaces and which is provided in a rotary compressor to compress a predetermined fluid is exemplified. Fig. 13(a) is a plan view showing an example of a workpiece, and fig. 13(b) is a side view along the arrow direction of fig. 13 (a).

In the conventional technique for machining the outer peripheral surface of the piston W, a cup-shaped grinding wheel having an annular grinding surface and the piston W are arranged such that their axes are perpendicular to each other, and the grinding surface is brought into contact with the outer peripheral surface of the piston W while the cup-shaped grinding wheel and the piston W are rotated on the axial center. The piston W is rotated forward and backward so that the vane (projection) Wa does not interfere with the cup-shaped grindstone.

However, in this grinding method, the grinding action surface of the cup-shaped grinding wheel is in line contact with the contact portion of the outer peripheral surface of the piston W, and only the contact portion of the grinding action surface is worn, which results in a problem of short grinding wheel life.

Therefore, as shown in japanese patent No. 2001-47344, a method is proposed in which a cup-shaped grindstone and a piston W are rotated on their respective axial centers, and the cup-shaped grindstone is moved relative to the piston W in a direction perpendicular to both the axis of the cup-shaped grindstone and the axis of the piston W, so that the contact position between the grinding action surface and the outer peripheral surface of the piston W can be changed as needed. Further, the piston W is rotated forward and backward so that the vane (projection) Wa does not interfere with the cup-shaped grindstone, as in the grinding method described above.

In this grinding method, since all the grinding working surfaces are in contact with the outer peripheral surface of the piston W, and the grinding working surfaces are subjected to relatively uniform wear, the life of the grinding wheel can be increased as compared with the above-described method.

However, in the grinding method disclosed in japanese patent No. 2001-47344, there is a problem that the relative reciprocating movement between the piston W and the grinding wheel is not completed even when the rotation of the piston W is completed, and therefore the period is long. In order to prevent such a problem, the relative reciprocating movement of the piston W and the grinding wheel may be synchronized with the rotation of the piston W, but the control of these operations becomes complicated to achieve synchronization.

Disclosure of Invention

The present invention has been made in view of the above problems, and an object of the present invention is to provide a grinding method and a grinding apparatus which can change a contact position between a cup-shaped grinding wheel and a workpiece by a simple operation without causing a problem of a long period and without performing complicated control, and can prevent only a part of a grinding action surface of the cup-shaped grinding wheel from being worn.

In order to achieve the above object, a grinding method of the present invention is characterized in that: a method for grinding the outer peripheral surface of a cylindrical workpiece by disposing a cup-shaped grinding wheel having an annular grinding surface and the workpiece so that their axes are perpendicular to each other, and rotating the cup-shaped grinding wheel and the workpiece on the axis while bringing the grinding surface into contact with the outer peripheral surface of the workpiece,

and under the state that the grinding action surface of the cup-shaped grinding wheel is contacted with the outer peripheral surface of the workpiece, the cup-shaped grinding wheel and the workpiece relatively move in the direction vertical to both the axis of the cup-shaped grinding wheel and the axis of the workpiece every time the workpiece rotates for a preset number of turns, and the position where the grinding action surface is contacted with the outer peripheral surface of the workpiece is changed.

Further, the grinding method can be preferably performed by the following grinding apparatus. Namely, the grinding device is characterized in that: the apparatus for grinding an outer peripheral surface of a workpiece processed in a cylindrical shape includes:

a workpiece holding device for holding the workpiece;

a first rotation driving mechanism that rotates the workpiece held by the workpiece holding device on an axis;

a cup-shaped grinding wheel having an annular grinding action surface, an axis of which is perpendicular to an axis of the workpiece;

a grinding wheel supporting device for supporting the cup-shaped grinding wheel to enable the cup-shaped grinding wheel to rotate freely on the axis;

a second rotation driving mechanism for rotating the cup-shaped grinding wheel on the axis;

a feed mechanism that relatively moves the workpiece holding device and the grinding wheel supporting device in a first axial direction parallel to an axis of the cup-shaped grinding wheel and a second axial direction perpendicular to both the first axis and the workpiece axis; and

a control device for driving the rotary drive mechanisms to rotate the workpiece and the cup-shaped grinding wheel and simultaneously driving the feed mechanism to move the workpiece holding device and the grinding wheel supporting device relative to each other in the first axial direction and to bring a grinding action surface of the cup-shaped grinding wheel into contact with an outer peripheral surface of the workpiece; wherein,

and the control device drives the feeding mechanism when the workpiece rotates for a preset number of turns under the state that the grinding action surface of the cup-shaped grinding wheel is contacted with the outer peripheral surface of the workpiece, so that the workpiece holding device and the grinding wheel supporting device relatively move in the second axial direction, and the contact position of the grinding action surface and the outer peripheral surface of the workpiece is changed.

According to this grinding apparatus, the control device drives the rotary drive mechanisms to rotate the workpiece and the cup-shaped grinding wheel on the axis, and drives the feed mechanism to move the workpiece holder and the grinding wheel support device relative to each other in the first axial direction so that the grinding action surface comes into contact with the outer peripheral surface of the workpiece, thereby grinding the outer peripheral surface of the workpiece by the grinding action surface of the cup-shaped grinding wheel.

In such a grinding process, the feed mechanism is driven by the control device for every predetermined number of rotations of the workpiece in a state where the grinding action surface of the cup-shaped grinding wheel is in contact with the outer peripheral surface of the workpiece, and the workpiece holding device and the grinding wheel supporting device are relatively moved in the second axial direction, thereby changing a position where the grinding action surface is in contact with the outer peripheral surface of the workpiece.

As described above, according to the grinding method and the grinding apparatus of the present invention, the cup-shaped grinding wheel and the workpiece are relatively moved in the second axial direction every time the workpiece rotates by a predetermined number of revolutions, and the position at which the grinding action surface contacts the outer peripheral surface of the workpiece is changed, whereby the occurrence of problems such as a long cycle can be avoided, and the contact position between the cup-shaped grinding wheel and the workpiece can be changed by a simple operation without performing complicated control. By changing the contact position in this manner, it is possible to prevent only a part of the grinding action surface of the cup-shaped grinding wheel from being worn, and to make the grinding action surface worn substantially uniformly, thereby extending the life of the grinding wheel.

In the grinding method and the grinding apparatus, the cup-shaped grinding wheel and the workpiece are relatively moved in the second axial direction for each preset number of rotations of the workpiece in grinding of one workpiece, but the cup-shaped grinding wheel and the workpiece may be relatively moved in the second axial direction for each predetermined number of workpieces to be machined when a plurality of workpieces are sequentially machined.

The workpiece is not limited to an absolutely cylindrical shape, and may be a workpiece having a projection on its outer peripheral surface.

Effects of the invention

As described above, according to the grinding method and the grinding apparatus of the present invention, the problem of the occurrence cycle length as in the conventional art does not occur, and the contact position between the cup-shaped grinding wheel and the workpiece can be changed by a simple operation without performing complicated control, so that only a part of the grinding action surface of the cup-shaped grinding wheel can be prevented from being worn, and the life of the grinding wheel can be improved.

Drawings

Fig. 1 is a plan view showing a schematic configuration of a grinding apparatus according to an embodiment of the present invention.

Fig. 2 is a side view in the direction of arrow a of fig. 1.

Fig. 3 is a sectional view in the direction of arrow B-B of fig. 1.

Fig. 4 is a sectional view in the direction of the arrow C-C of fig. 3.

Fig. 5 is a sectional view in the direction of arrows D-D of fig. 1.

Fig. 6 is a side view in the direction of arrow E of fig. 5.

Fig. 7 is a side view in the direction of arrow F of fig. 6.

Fig. 8 is a sectional view in the direction of arrows G-G of fig. 1.

Fig. 9 is a plan view of a schematic configuration of the supply unit in the present embodiment.

Fig. 10 is a sectional view in the direction of the arrow H-H of fig. 9.

Fig. 11 is an explanatory diagram showing the rotation direction of the workpiece and the positional relationship between the cup-shaped grindstone and the workpiece.

Fig. 12 is an explanatory diagram showing the rotation direction of the workpiece and the positional relationship between the cup wheel and the workpiece.

Fig. 13 is an explanatory diagram showing a schematic configuration of a workpiece.

Description of the symbols:

1-grinding device

5-base station

6-control device

10-grinding wheel support part of automobile

11-rubstone head

14-rubstone slide block

18-feeding section

19-first feed mechanism

25-second feed mechanism

30-workpiece holding part

31-main shaft

34-clamping head (Collet)

35-tailstock (tail stock)

39-pressing part

45-positioning chuck

50-measuring part

52-Loading part

53-pressing part

56-measuring head

60-supply part

61-rotating part

62-workpiece loading plate

70-dressing (stress) part

P-supply discharge device

Q-machining position

R-measurement position

T-cup (cup) shaped grinding wheel

W-workpiece (work)

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the drawings. Fig. 1 is a plan view showing a schematic structure of a grinding apparatus according to an embodiment of the present invention, fig. 2 is a side view in the direction of arrow a in fig. 1, fig. 3 is a sectional view in the direction of arrows B-B in fig. 1, fig. 4 is a sectional view in the direction of arrows C-C in fig. 3, fig. 5 is a sectional view in the direction of arrows D-D in fig. 1, fig. 6 is a side view in the direction of arrow E in fig. 5, and fig. 7 is a side view in the direction of arrow F in fig. 6. Fig. 8 is a sectional view taken along the direction of arrows G-G in fig. 1, fig. 9 is a plan view showing a schematic configuration of the supply unit in the embodiment, and fig. 10 is a sectional view taken along the direction of arrows H-H in fig. 9.

As shown in fig. 1, the grinding apparatus 1 of the present example is configured to include the following components: a workpiece holding section 30 for holding a workpiece W; a cup-shaped grinding wheel T having an annular grinding action surface Ta and grinding an outer peripheral surface of the workpiece W by the grinding action surface Ta; a grindstone support portion 10 having a horizontal axis and supporting a cup-shaped grindstone T so as to be movable in a direction perpendicular to two axes (a first axis and a second axis to be described later); a feed unit 18 for moving the cup-shaped grinding wheel T in the two vertical directions; a measuring section 50 for measuring the outer diameter of the workpiece W after grinding; a supply unit 60 that supplies the workpiece W to the workpiece holding unit 30 and the measuring unit 50; a dressing section 70 for dressing the cup-shaped grinding wheel T; a base 5 on which the workpiece holding portion 30, the grinding wheel supporting portion 10, the measuring portion 50, the supplying portion 60, and the dressing portion 70 are disposed; and a control device 6 for controlling the operations of the workpiece holding section 30, the feeding section 18, the measuring section 50, the supplying section 60, and the trimming section 70.

As shown in fig. 1 to 4, the grinding wheel support portion 10 includes: a grinding stone 11 having a first member 12 for rotatably supporting the cup-shaped grinding wheel T on an axial center thereof, and a second member 13 for movably supporting the first member 12 in a first axial direction parallel to an axis of the cup-shaped grinding wheel T; a drive motor (not shown) which is built in the first member 12 and rotates the cup-shaped grinding wheel T on the axis; the grindstone slider 14, the second member 13 on which the grindstone 11 is mounted, is provided on the base 5 so as to be movable in a second axial direction perpendicular to the first axis in the horizontal plane. The operation of the motor, not shown, is controlled by the control device 6.

The first member 12 has coupling protrusions 12a protruding to both sides in the horizontal direction and formed along the longitudinal direction, and the second member 13 is provided with a receiving portion 13a for receiving the first member 12 and coupling grooves 13b opened in the inner surface of the receiving portion 13a and respectively coupled to the coupling protrusions 12a of the first member 12. Further, a slider 14a movably coupled to a guide rail 5a provided on the base 5 in parallel with the second axis is attached to the bottom surface of the whetstone slider 14.

The feeding portion 18 includes the following structure: a first feed mechanism 19 for moving the first member 12 (cup grinding wheel T) of the grinding stone 11 in the first axial direction; and a second feed mechanism 25 for moving the grindstone block 14 (cup grinding wheel T) in the second axial direction.

The first feeding mechanism 19 includes: a drive motor 20 provided on the second member 13 of the grinding stone 11, the operation of which is controlled by the control device 6; a worm 21 rotatably supported on an axis of the second member 13 and rotated by a drive motor 20; a worm wheel 22 meshed with the worm 21; a nut 23 rotatably supported on the inner axial center of the second member 13 and fixed to the worm wheel 22; the ball screw 24 is disposed with its axis parallel to the first axis and is screwed to the nut 23, and a bracket 12b formed on the bottom surface of the first member 12 is connected to one end of the ball screw 24.

On the other hand, the second feeding mechanism 25 includes: a drive motor 26 provided on the base 5 and controlled by the control device 6 to operate; a ball screw 27 having an axis parallel to the second shaft and rotated on the axis thereof by a drive motor 26; and a nut 28 fixed to the whetstone block 14 and screwed to the ball screw 27.

In this way, in the first feed mechanism 19, when the drive motor 20 is driven to rotate the worm 21 on the axial center, the rotational force is transmitted to the worm wheel 22 to rotate the nut 23, and the ball screw 24 is moved in the axial direction thereof, so that the first member 12 is moved in the first axial direction by the guide of the coupling projection 12a and the coupling groove 13 b. In the second feed mechanism 25, the ball screw 27 is rotated on the axial center by driving the drive motor 26, and the nut 28 is moved in this direction, whereby the grindstone block 14 is moved in the second axial direction by being guided by the guide rail 5a and the block 14 a.

The workpiece holding portion 30 is configured to hold the workpiece W as shown in fig. 13, which has a protrusion Wa formed on an outer peripheral surface and a through hole Wb opened at both end surfaces, and has a configuration in which an axis is arranged parallel to a vertical direction as shown in fig. 1 and 5 to 7, and includes: a spindle 31, a spindle support member 32, a spindle rotation drive mechanism (not shown), a clamp mechanism 33, and a tailstock 35, wherein: the spindle 31 has an axis arranged parallel to the vertical direction and a bearing portion 31a at an upper end thereof for bearing the workpiece W thereon; a spindle support member 32 provided on the base 5 and supporting the spindle 31 rotatably on the axis thereof; the spindle rotation driving mechanism rotationally drives the spindle 31 on the axis; the chuck mechanism 33 is constituted by a chuck 34 or the like which grips the inner peripheral surface of the through hole Wb of the workpiece W mounted on the mounting portion 31a of the spindle 31; the tailstock 35 presses the upper surface of the workpiece W loaded on the loading portion 31a of the spindle 31.

The tail stock 35 includes a support arm 36, a guide rail 37, a moving member 38, a lifting mechanism 42, a pressing member 39, a support block 40, a connecting member 41, and a positioning chuck 45, wherein: the support arm 36 is arranged on the base 5; the guide rail 37 is provided in the vertical direction, and is supported by the support arm 36; the moving member 38 is provided with a slider 38a which is freely movable in conjunction with the guide rail 37; the lifting mechanism 42 lifts and lowers the moving member 38 under the guide of the guide rail 37 and the slider 38 a; the pressing member 39 has an annular abutting surface 39a formed on the lower surface thereof and abutting against the upper surface of the workpiece W; the supporting block 40 supports the pressing member 39 to be horizontally freely rotatable; the connecting member 41 connects the lower surface of the moving member 38 with the upper surface of the supporting block 40; the positioning chuck 45 positions the rotation direction of the workpiece W mounted on the mounting portion 31a of the spindle 31.

The lifting mechanism 42 comprises a pneumatic cylinder 43 and a spring body 44, wherein the pneumatic cylinder 43 is fixed on the supporting arm 36 and is provided with a lifting rod 43a connected with the upper surface of the moving part 38; the spring body 44 has one end connected to the support arm 36 and the other end connected to the moving member 38, and applies an upward force to the moving member 38, wherein the lifting/lowering rod 43a is lowered by the operation of the pneumatic cylinder 43 to lower the moving member 38, and the abutting surface 39a of the pressing member 39 abuts on the upper surface of the workpiece W. Further, since the spring body 44 has a weight equivalent to the moving member 38, the support block 40, and the like, it is possible to prevent the lifting lever 43a from being rapidly lowered, and also to function to smoothly operate the lifting lever 43a when it is lifted.

The positioning chuck 45 is provided with a gripping claw 46, an opening/closing mechanism 47, and a pneumatic cylinder 48, wherein: the gripping claws 46 can grip both side surfaces of the projecting portion Wa of the workpiece W; an opening/closing mechanism 47 for opening and closing the holding claw 46 while supporting it; the pneumatic cylinder 48 is attached to a bracket 49 fixed to the support arm 36, and supports the opening/closing mechanism 47 (gripping claw 46) to be raised and lowered in an oblique direction.

The operation of the spindle rotation driving mechanism (not shown), the chuck mechanism 33, the pneumatic cylinder 43 of the elevating mechanism 42, the opening and closing mechanism 47 of the positioning chuck 45, and the pneumatic cylinder 48 is controlled by the control device 6.

The measuring part 50 includes a support table 51, a loading member 52, a clamping mechanism (not shown), a pressing member 53, a pneumatic cylinder 54, a support arm 55, a measuring head 56, and a pneumatic cylinder 58, wherein the support table 51 is disposed on the base 5; the loading member 52 is fixed to the support table 51, and a workpiece W is loaded thereon; a through hole through which the jig mechanism clamps the workpiece W loaded on the loading member 52; the pressing member 53 is provided above the loading member 52, and has a contact surface 53a formed on the lower surface thereof to be connected to the upper surface of the workpiece W; the pneumatic cylinder 54 has a vertically-disposed lifting rod 54a that contacts the upper surface of the pressing member 53, and the contact surface 53a contacts the upper surface of the workpiece W by lowering the lifting rod 54a to lower the pressing member 53; a support arm 55 provided on the support base 51 for supporting the pneumatic cylinder 54; the measuring head 56 measures the outer diameter of the workpiece W; the pneumatic cylinder 58 is fixed to the support base 51, and supports the measuring head 56 via the connecting member 57 so as to move in the second axial direction. The clamping mechanism (not shown), the pneumatic cylinder 54, the pneumatic cylinder 58, and the measuring head 56 are controlled by the control device 6.

As shown in fig. 1, 9 and 10, the supply unit 60 includes: a rotating member 61, three workpiece loading plates 62, a support member 63, and a drive mechanism (not shown), wherein the workpiece loading plates 62 are mounted on the rotating member 61 at equal intervals in the circumferential direction; a support member 63 provided on the base 5 and supporting the rotary member 61 to be horizontally rotatable in the arrow direction and movable in the vertical direction; the driving mechanism rotates the rotating member 61 in the horizontal direction and moves it in the vertical direction.

The workpiece mounting plate 62 is provided with a recess 62a for mounting the workpiece W, and is formed in a shape substantially identical to the outer shape of the workpiece W such that the projecting portion Wa of the workpiece W faces the rotation center of the rotating member 61 and the axis of the workpiece W faces the vertical direction, and a through hole 62b slightly larger than the outer diameters of the spindle 31 and the mounting member 52 is formed in the recess 62 a.

The drive mechanism (not shown) is configured to rotate the rotary member 61 horizontally, and to define the workpiece loading plate 62 (the workpiece W loaded on the workpiece loading plate 62) at the supply/discharge position P, the machining position Q (the position above the main shaft 31 of the workpiece holding portion 30), and the measurement position R (the position above the loading member 52 of the measurement portion 50) in the rotation direction, and the operation thereof is controlled by the control device 6.

The dressing section 70 is configured to rotate the

dressers

71 and 72 in the arrow direction while rotating the dressers on the axial center, and is configured to dress the grinding action surface Ta of the cup-shaped grinding wheel T by using the outer peripheral surface thereof.

The control device 6 drives a drive motor (not shown) and a spindle rotation drive mechanism (not shown) to rotate the cup wheel T and the spindle 31 (i.e., the workpiece W) about their respective axes, and drives the first feed mechanism 19 and the second feed mechanism 25 to move the first member 12 of the grindstone 11 in the first axial direction and the grindstone slider 14 in the second axial direction, respectively, that is, to move the cup wheel T in two perpendicular axial directions, so that the grinding action surface Ta of the cup wheel T comes into contact with the outer peripheral surface of the workpiece W to perform rough grinding and finish grinding, respectively, on one workpiece W.

In the rough grinding, the control device 6 rotates the workpiece W in the normal direction without interference between the projections Wa and the cup grindstone T, and the projections Wa of the workpiece W are brought into close proximity to the outer peripheral surface of the cup grindstone T from a state in which the projections Wa of the workpiece W are brought into close proximity to the inner peripheral surface of the cup grindstone T; the above operations are alternately repeated from a state in which the projections Wa of the workpiece W are close to the outer peripheral surface of the cup grindstone T to a state in which the projections Wa of the workpiece W are close to the inner peripheral surface of the cup grindstone T, and when switching from normal rotation to reverse rotation and from reverse rotation to normal rotation, the cup grindstone T is moved in the second axial direction so that the grinding action surface Ta of the cup grindstone T is in contact with the outer peripheral surface of the workpiece W, and the cup grindstone T is moved in the first axial direction toward the workpiece W so as to have a predetermined depth of cut while changing the width direction position of the grinding action surface Ta.

Specifically, for example, as shown in fig. 11(a) and (a '), the workpiece W is rotated in the forward direction, the portion Pa inside the center line L of the grinding action surface Ta is in contact with the outer peripheral surface of the workpiece W, then, as shown in fig. 11(b) and (b'), the workpiece W is rotated in the reverse direction, the portion Pa outside the center line L of the grinding action surface Ta is in contact with the outer peripheral surface of the workpiece W, then, as shown in fig. 11(c) and (c '), the workpiece W is rotated in the forward direction, the portion Pc on the outer edge side of the grinding action surface Ta is in contact with the outer peripheral surface of the workpiece W, and then, as shown in fig. 11(d) and (d'), the workpiece W is rotated in the reverse direction, and the portion Pd on the inner edge side of the grinding action surface Ta is in contact with the.

On the other hand, in the finish grinding, for example, as shown in fig. 11(e) and (e'), the cup grindstone T is moved in the second axial direction so that the contact position Pe between the grinding action surface Ta of the cup grindstone T and the outer peripheral surface of the workpiece W becomes an intermediate position in the width direction of the grinding action surface Ta, the cup grindstone T is moved in the first axial direction toward the workpiece W so as to have a predetermined cut amount, and then the workpiece W is rotated in the forward direction so that the protrusion Wa of the workpiece W comes close to the inner peripheral surface of the cup grindstone T, without interference between the protrusion Wa and the cup grindstone T.

When the grinding of one workpiece W is completed, the controller 6 controls to grind a new unprocessed workpiece W, but at this time, as shown in fig. 12, the workpiece W is rotated in the opposite direction to the example shown in fig. 11. That is, in the example shown in fig. 11, the workpiece W is rotated in the order of forward rotation, reverse rotation, and forward rotation, whereas in the example shown in fig. 12, the workpiece W is rotated in the order of reverse rotation, forward rotation, and reverse rotation. In this way, the controller 6 continuously and alternately executes the sequence shown in fig. 11 and the sequence shown in fig. 12, that is, the sequence of the rotational direction of the workpiece W is alternately changed, and the grinding of the plurality of workpieces W can be continuously performed.

The grinding apparatus 1 of the present embodiment configured as described above performs continuous grinding of a plurality of workpieces W as described below. That is, first, the first workpiece W is loaded on the workpiece loading plate 62 located at the supply/discharge position P, and the rotary member 61 is raised simultaneously with the workpiece loading plate 62 and then horizontally rotated, thereby moving the workpiece loading plate 62 located at the supply/discharge position P to the machining position Q.

Thereafter, when the rotary member 61 is lowered, the workpiece W on the workpiece loading plate 62 is loaded on the loading portion 31a of the main spindle 31 while the collet 34 of the chuck mechanism 33 is inserted into the through hole Wb of the workpiece W. Then, the rotating member 61 and the workpiece loading plate 62 are lowered to the lowered end position. At the same time, a second workpiece W is loaded on the workpiece loading plate 62 located at the supply/discharge device P.

Subsequently, the opening and closing mechanism 47 and the gripping claws 46 of the positioning chuck 45 are lowered, and the gripping claws 46 are closed by the opening and closing mechanism 47. Thus, the projecting portion Wa of the workpiece W is gripped by the gripping claws 46, and the position of the workpiece W in the rotational direction is determined.

Next, the pressing member 39 is lowered by the elevating mechanism 42, and the contact surface 39a thereof comes into contact with the upper surface of the workpiece W, so that the workpiece W is held by the pressing member 39 and the loading portion 31a of the spindle 31. Then, the inner peripheral surface of the through hole Wb of the workpiece W is clamped by the chuck 34, and thereafter, the gripping claws 46 are opened, and the opening/closing mechanism 47 and the gripping claws 46 are raised.

Thereafter, under the control of the control device 6, the rotation of the workpiece W and the positions of the cup grindstones T in the two vertical axial directions are controlled as described above, and when the outer peripheral surface of the workpiece W is ground, the clamping of the inner peripheral surface of the through hole Wb of the workpiece W is released by the chuck 34 while the pressing member 39 is lifted by the lifting mechanism 42.

Next, the rotating member 61 is raised, and during the raising, the workpiece W on the loading portion 31a of the main spindle 31 is loaded on the workpiece loading plate 62 and raised to a raised end position. Further, when the rotating member 61 is rotated horizontally, the workpiece loading plate 62 located at the machining position Q is moved to the measuring position R, and the workpiece loading plate 62 located at the supply/discharge device P is moved to the machining position Q.

Next, when the rotating member 61 is lowered, the first workpiece W loaded on the workpiece loading plate 62 at the measurement position R is loaded on the loading member 52 in the middle of the lowering, and the rotating member 61 and the workpiece loading plate 62 are lowered to the lowered end position. Thereafter, the workpiece W on the mounting member 52 is clamped on the inner peripheral surface of the through hole Wb by a clamp mechanism (not shown), and the pressing member 53 is lowered to contact the upper surface, whereby the workpiece W is clamped by the pressing member 53 and the mounting member 52.

Then, the measuring head 56 moved toward the second axial direction workpiece W by the pneumatic cylinder 58 measures the outer diameter of the workpiece W to check whether or not the outer diameter is within a predetermined dimension range, and thereafter, the measuring head 56 is moved in the second axial direction away from the workpiece W, and the pressing member 53 is raised, and the chuck mechanism (not shown) releases the clamping of the inner peripheral surface of the through hole Wb of the workpiece W.

On the other hand, by lowering the rotary member 61, the second workpiece W loaded on the workpiece loading plate 62 located at the machining position Q is loaded on the loading portion 31a of the spindle 31 while being lowered, and the collet 34 is inserted into the through hole Wb. In addition, grinding can be performed after the fixing as described above, and in this case, the rotation direction of the second workpiece W is reversed compared with the case of the first workpiece W. Wherein a third workpiece W is loaded on the workpiece loading plate 62 located at the supply/discharge device P.

Thereafter, when the rotary member 61 is raised, the respective workpieces W on the loading portion 31a of the main spindle 31 and the loading member 52 are loaded on the workpiece loading plate 62 and raised to the raised end position, and the workpiece loading plate 62 located at the measurement position R is moved to the supply/discharge device P, the workpiece loading plate 62 located at the processing position Q is moved to the measurement position R, and the workpiece loading plate 62 located at the supply/discharge device P is moved to the processing position Q by the horizontal rotation of the rotary member 61.

When the rotating member 61 is lowered, the second and third workpieces W are respectively mounted on the mounting member 52 and the mounting portion 31a of the spindle 31, and the outer diameter dimension measurement and the grinding are performed. In the grinding of the third workpiece W, the rotation direction thereof is reversed from that of the second workpiece W, that is, the same as that of the first workpiece W. On the other hand, the first workpiece W is discharged from the workpiece loading plate 62, and a fourth workpiece W is loaded.

Thereafter, the above operation is repeated to perform grinding, and the workpiece W is sequentially ground by the grinding apparatus 1 until the nth one.

As described above, according to the grinding apparatus 1 of the present invention, the cup-shaped grinding wheel T moves in the second axial direction to change the contact position of the grinding action surface Ta with the outer peripheral surface of the workpiece W every time the workpiece W rotates one round (every time the rotation direction of the workpiece W is changed), and therefore, the problem of a long cycle does not occur, and the contact position of the grinding action surface Ta with the outer peripheral surface of the workpiece can be changed by a simple operation without performing complicated control. By changing the contact position in this manner, it is possible to prevent only a part of the grinding action surface Ta of the cup-shaped grinding wheel T from being worn, and to substantially uniformly wear the grinding action surface Ta, thereby extending the life of the grinding wheel.

Further, since the rotation direction of each workpiece W is changed in the forward and reverse order, it is possible to prevent the occurrence of variations in the amount of wear of the grinding action surface Ta of the cup-shaped grinding wheel T due to variations in the grinding cost of the workpiece W and the like, and to make the wear applied to the grinding action surface Ta of the cup-shaped grinding wheel T more uniform.

While one embodiment of the present invention has been described above, the specific form that can be adopted by the present invention is not limited to the above embodiment.

In the above example, the contact position between the grinding action surface Ta of the cup-shaped grinding wheel T and the outer peripheral surface of the workpiece during the rough grinding is changed in the order of the portion Pa inside the center line L of the grinding action surface Ta, the portion Pb outside the center line L of the grinding action surface Ta, the outer edge side portion Pc of the grinding action surface Ta, and the inner edge side portion Pd of the grinding action surface Ta.

The contact position of the grinding action surface Ta with the outer peripheral surface of the workpiece is changed between four portions, but the present invention is not limited to this, and may be changed between three portions, for example, the center portion in the width direction of the grinding action surface Ta, the outer edge side portion of the grinding action surface Ta, and the inner edge side portion of the grinding action surface Ta.

Further, the contact position of the grinding operation surface Ta with the outer peripheral surface of the workpiece W is changed every time the workpiece W rotates once (every time the rotation direction of the workpiece W is changed), but the contact position of the grinding operation surface Ta with the outer peripheral surface of the workpiece W may be changed every time the workpiece W rotates multiple times (every time the rotation direction of the workpiece W is changed multiple times), and the order of the forward direction and the reverse direction of the rotation direction of the workpiece W may be changed not every time one workpiece W is machined but every time a plurality of workpieces W are machined.

Further, the position at which the grinding action surface Ta contacts the outer peripheral surface of the workpiece W may be changed for each grinding of one workpiece W or for each grinding of a plurality of workpieces W.

The workpiece W is not limited to a workpiece having the projecting portion Wa on the outer peripheral surface, and may be a completely cylindrical workpiece.

Claims

1. A grinding method is characterized in that:

the grinding method is a method for sequentially grinding the outer peripheral surfaces of a plurality of cylindrical workpieces,

the grinding method comprises disposing a cup-shaped grinding wheel having an annular grinding action surface and a workpiece so that respective axes of the cup-shaped grinding wheel and the workpiece are perpendicular to each other, rotating the cup-shaped grinding wheel about the axis of the cup-shaped grinding wheel, rotating the workpiece forward and backward about the axis of the workpiece, and bringing the grinding action surface into contact with an outer peripheral surface of the workpiece, thereby grinding the outer peripheral surface of the workpiece,

after the outer peripheral surface of the workpiece is machined by rotating the workpiece forward and backward more than once, the cup-shaped grinding wheel and the workpiece are relatively moved in a direction perpendicular to both the axis of the cup-shaped grinding wheel and the axis of the workpiece, the contact position of the grinding action surface and the outer peripheral surface of the workpiece is changed, and then the outer peripheral surface of the workpiece is machined by rotating the workpiece forward and backward more than once again,

starting rotation of each of the workpieces from one of the forward and reverse directions for one or more workpieces to be machined in sequence, then reversing the direction of rotation in sequence, starting rotation of each of the workpieces from the other of the forward and reverse directions for one or more workpieces to be machined subsequently, then reversing the direction of rotation in sequence, and after one or more workpieces have been machined, reversing the direction of rotation of one or more workpieces to be machined subsequently.

2. A grinding method is characterized in that:

machining the outer peripheral surface of each pair of one or more workpieces, relatively moving the cup-shaped grinding wheel and the workpiece in a direction perpendicular to both the axis of the cup-shaped grinding wheel and the axis of the workpiece, changing the contact position of the grinding action surface with the outer peripheral surface of the workpiece, and,

3. A kind of grinding processing device, characterized by:

the grinding device is a device for sequentially grinding the outer peripheral surfaces of a plurality of cylindrical workpieces, and comprises:

a workpiece holding device for holding the workpiece;

a first rotation driving mechanism that rotates the workpiece held by the workpiece holding device around an axis of the workpiece;

a cup-shaped grinding wheel having an annular grinding action surface, an axis of the cup-shaped grinding wheel being disposed perpendicular to an axis of the workpiece;

a grinding wheel supporting device for supporting the cup-shaped grinding wheel so that the cup-shaped grinding wheel can rotate freely around the axis of the cup-shaped grinding wheel;

a second rotation driving mechanism for rotating the cup-shaped grinding wheel around the axis of the cup-shaped grinding wheel;

a feed mechanism that relatively moves the workpiece holding device and the grinding wheel supporting device in a direction along a first axis parallel to an axis of the cup-shaped grinding wheel and in a direction along a second axis perpendicular to both the first axis and the axis of the workpiece; and

a control device for driving the first rotary drive mechanism to rotate the workpiece forward and backward, driving the second rotary drive mechanism to rotate the cup-shaped grinding wheel, and driving the feed mechanism to move the workpiece holding device and the grinding wheel support device relative to each other in the direction of the first axis, thereby bringing the grinding action surface of the cup-shaped grinding wheel into contact with the outer peripheral surface of the workpiece,

the control device is configured to, after the workpiece is rotated forward and backward one or more times to machine the outer peripheral surface of the workpiece, move the workpiece holding device and the grinding wheel supporting device relative to each other in the direction of the second axis to change the contact position between the grinding action surface and the outer peripheral surface of the workpiece, and then rotate the workpiece forward and backward one or more times to machine the outer peripheral surface of the workpiece again,

and starting rotation of each of the workpieces from one of the forward and reverse directions for one or more workpieces to be machined in sequence, and then reversing the direction of rotation in sequence, starting rotation of each of the workpieces from the other of the forward and reverse directions for one or more workpieces to be machined thereafter, and then reversing the direction of rotation in sequence, and after one or more workpieces have been machined, reversing the direction of rotation of one or more workpieces to be machined thereafter.

4. A kind of grinding processing device, characterized by:

a workpiece holding device for holding the workpiece;

a cup-shaped grinding wheel having an annular grinding action surface, the cup-shaped grinding wheel having an axis arranged perpendicular to an axis of the workpiece;

a control device for driving the first rotary drive mechanism to rotate the workpiece forward and backward, driving the second rotary drive mechanism to rotate the cup-shaped grinding wheel, and driving the feed mechanism to move the workpiece holding device and the grinding wheel support device relative to each other in the direction along the first axis, thereby bringing the grinding action surface of the cup-shaped grinding wheel into contact with the outer peripheral surface of the workpiece,

the control device is configured to change a contact position between the grinding action surface and the outer peripheral surface of the workpiece by relatively moving the workpiece holding device and the grinding wheel supporting device in the direction of the second axis every time one or more workpieces are rotated in the forward and reverse directions to machine the outer peripheral surface of the workpiece,

and starting rotation of each of the workpieces from one of the forward and reverse directions for one or more workpieces to be sequentially machined, then sequentially reversing the direction of rotation, starting rotation of each of the workpieces from the other of the forward and reverse directions for one or more workpieces to be subsequently machined, then sequentially reversing the direction of rotation, and after one or more workpieces have been machined, reversing the direction of rotation of one or more workpieces to be subsequently machined.