JP2002113659A - Method of grinding by grinder and grinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinder capable of reducing the frequency of suspending the grinding operation of a work for regenerating the grinding performance of a rotary grinding wheel. SOLUTION: A column 12 is erected on a base 11, and a spindle head 13 is supported in the column 12 in such a way that the main shaft head can be moved up/down. A saddle 20 is mounted on the base 11 in such a way that the saddle can be moved forward/backward, and a table 22 is supported on the top of the saddle 20 in such a way that the table can be moved in the left/right directions. A motor 17 for rotation, which can rotate in both ways, is disposed at the spindle head 13 on the rear side of the column 12, and a rotary grinding wheel 19 is fixed to the rotation axis 18 of the motor 17 for rotation in such a way that the rotary grinding wheel 19 can be integrally rotated. An acoustic emission sensor (AE sensor) 26 is disposed as a detector in a position opposite to a work 25 on the front side of the column 12. The AE sensor 26 detects the deterioration of the grinding performance of the rotary grinding wheel 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding method and a grinding machine in a grinding machine, and more particularly, to a rotary grinding wheel which is relatively moved along a surface to be ground of a work while being rotated by a rotating motor. The present invention relates to a grinding method and a grinding machine in a grinding machine for grinding a surface to be ground of the work with abrasive grains contained in the grinding machine.

[0002]

2. Description of the Related Art Conventionally, there is a grinding machine in which a work held on a work table of a grinding machine is ground by a disk-shaped rotary grindstone. As shown in FIG. 5A, the rotary grindstone 41 includes abrasive grains 42 and an adhesive bond 43 that bonds the abrasive grains 42 together. Bond 43
Is lower in strength than the abrasive grains 42, and the work 4
In order to grind the grinding wheel 4, it is preferable that the abrasive grains 42 protrude by a certain length with respect to the bond 43 on the peripheral surface of the rotating grindstone 41 in contact with the work 44, since the grinding ability (sharpness) is good. . However, the work 4
When grinding 4, the protruding abrasive grains 42 are gradually worn, and shavings 45 accumulate on the front side in the rotation direction of the abrasive grains 42, and the grinding ability is reduced. When the grinding ability is significantly reduced, as shown in FIG. 5B, the bond 43 is cut with, for example, a cutting tool 46 to secure the amount of protrusion of the abrasive grains 42 with respect to the bond 43, and the chip 45 is removed and the rotation is performed. The grinding ability of the whetstone was being regenerated.

[0003]

However, the byte 46
As a result, the work of grinding the work 44 is interrupted every time the bond 43 is cut, and the work of cutting the bond 43 is also troublesome. As a result, the operation efficiency of the grinding machine is reduced due to an increase in the number of interruptions, and the cost increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a grinding machine capable of reducing the number of times of interrupting a work grinding operation to regenerate a grinding ability of a rotary grinding wheel. An object of the present invention is to provide a grinding method and a grinder.

[0005]

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a rotating grindstone is relatively moved along a surface to be ground of a work while being rotated by a rotating motor. In a grinding machine that grinds the surface to be ground of the work with abrasive grains contained in the rotating grindstone, at the time of grinding, the rotating grindstone is first rotated in a predetermined direction, and when the grinding ability of the rotating grindstone is reduced, the rotating The gist is that the grinding wheel is rotated in the reverse direction to continue the grinding.

According to the present invention, when the abrasive grains are worn by the forward rotation of the rotary grindstone and the swarf of the work accumulates on the front side in the rotational direction of the abrasive grains and the grinding ability is greatly reduced, the rotary grindstone is rotated in the reverse direction. Grinding continues. Therefore, the grinding is continued without regenerating the grinding ability of the rotating grindstone until the grinding ability of the rotating grindstone is reduced not only in the normal rotation but also in the reverse rotation. The number of times the grinding operation is interrupted can be reduced, and the cost can be reduced.

According to a second aspect of the present invention, the grinding surface of the workpiece is relatively moved along the surface to be ground of the workpiece while the rotating grinding wheel is rotated by the rotating motor, and the abrasive grains contained in the rotating grinding stone. In a grinding machine for grinding, the grit of the present invention is characterized in that the rotating grindstone is fixed to a rotating shaft rotated by the rotating motor so as to be integrally rotatable, and the rotating motor is formed so as to be capable of normal and reverse rotation. According to this invention, as in the first aspect of the invention, the grinding is continued without performing the operation of regenerating the grinding ability of the rotary grindstone until the grinding ability of not only the normal rotation but also the reverse rotation of the rotary grindstone is reduced. .

According to a third aspect of the present invention, in the invention according to the second aspect, the grinding machine is provided with a detecting device for detecting that the grinding ability of the rotary grindstone has decreased. The gist is that the rotating grindstone is reversely rotated after the reduction of the grinding ability of the rotating grindstone is detected. According to the present invention, the rotation direction of the rotary grindstone is switched at an appropriate time without causing a state in which the switching time is too late or too early.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of a grinding machine embodying the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, a column 12 is erected on a base 11 of a grinding machine 10. Column 1
2, a spindle head 13 is supported via a pair of rails 14 so as to be able to move up and down.
6 to be moved up and down. On the back side of the column 12, a rotation motor 17 is arranged on the spindle head 13. The rotation motor 17 is formed so as to be capable of normal and reverse rotation. A rotation shaft 18 of the rotation motor 17 penetrates through the spindle head 13 and protrudes toward the front side of the column 12. On the front side of the column 12, a rotating grindstone 19 is fixed to the rotating shaft 18 so as to be integrally rotatable. The rotating grindstone 19 rotates integrally with the rotating shaft 18 and rotates the rotating motor 17.
Rotates forward and backward in accordance with the forward and reverse rotation of.

A saddle 20 is provided on the base 11 so as to be movable in a front-rear direction (a direction orthogonal to the paper surface) in FIG. A table 22 is supported on a pair of rails 21 provided on the upper surface of the saddle 20 so as to extend in the left and right directions in FIG. 1 so as to be movable in the left and right directions, and is moved by a movement motor 23 via a ball screw 24. ing. A work 25 is detachably supported on the table 22 so as to be detachable from the rotary grindstone 19.

On the front side of the column 12, an acoustic emission sensor (hereinafter abbreviated as AE sensor) 26 is disposed at a position facing the work 25 as a detecting device for detecting that the grinding ability of the rotary grindstone 19 has decreased. Have been. The AE sensor 26 is relatively inexpensive. The AE sensor 26 is connected to a control device (not shown). The control device is connected to a rotation motor 17. The control device receives the output signal of the AE sensor 26 and switches the rotation direction of the rotation motor 17 when determining that the grinding ability of the rotary grindstone 19 has decreased.

[0013] As shown in FIG.
Is composed of abrasive grains 32 and an adhesive bond 33 that bonds the abrasive grains 32 together. Bond 33 is abrasive 3
The strength is lower than 2.

Next, the operation of the grinding machine 10 will be described. First, the work 25 is fixed on the table 22. The spindle head 13 is moved up and down by the elevating motor 15, and the rotating grindstone 19 is moved to the ground surface 25 a of the work 25 on the table 22.
It is arranged at a position where it can contact with. Next, the rotation motor 1
The table 25 is moved in the left and right direction by the moving motor 23 while the rotating grindstone 19 is being rotated by 7, so that the work 25 is relatively moved in the left and right direction with respect to the rotating grindstone 19 and The grinding surface 25a is ground. Next, the saddle 20 is moved to change the position of the ground surface 25a in contact with the rotary grindstone 19, and grinding is performed in the same manner.

Next, the state near the abrasive grains 32 will be described in detail. As shown in FIG. 3 (a), when the rotating grindstone 19 is rotated counterclockwise (forward rotation) to grind the grinding surface 25a, the abrasive grains 32 gradually wear, and the abrasive grains 32 rotate in the front side in the rotation direction. The swarf 35 a accumulates in the grinding wheel, and the grinding ability of the rotary grindstone 19 decreases. When the wear and accumulation of the swarf 35 a progress and the grinding ability of the rotary grindstone 19 greatly decreases, the decrease in the grinding ability is detected by the AE sensor 26. Based on the output signal of the AE sensor 26, the control device drives the rotation motor 17 to rotate in the reverse direction, and as shown in FIG.
Grinding of 5a is continued. Even in this reverse rotation, the abrasive grains 32 are worn, and the shavings 35 b accumulate on the rear side in the rotation direction of the abrasive grains 32. Grinding by the reverse rotation of the rotating grindstone 19
The wear and accumulation of the swarf 35 b continue until the grinding ability of the rotary grindstone 19 decreases. When the grinding ability is significantly reduced, the AE sensor 26 detects the sharp decrease, and the control device interrupts the grinding. 5B, the bond 33 is shaved by a cutting tool (not shown), so that the amount of protrusion of the abrasive grains 32 with respect to the bond 33 is secured, and the shavings 35a, 35b are removed. The grinding ability of the rotary grindstone 19 is regenerated. Thereafter, the rotating grindstone 19 is rotated counterclockwise again to grind the surface 25a to be ground.

As described in detail above, according to this embodiment, the following effects can be obtained. (1) When the grinding ability of the rotating grindstone 19 decreases due to the normal rotation, the rotating grindstone 19 is rotated in the reverse direction to continue the grinding. Therefore, since the grinding is continued without interruption until the grinding ability of the rotating grindstone 19 in the forward and reverse rotations is reduced, the number of times the grinding work of the work 25 is interrupted to regenerate the grinding ability of the rotating grindstone 19 is reduced. And lower costs.

(2) Since the rotation motor 17 is formed so as to be able to rotate forward and backward, the rotating grindstone 19 can be rotated forward and backward with a simple structure. (3) Since the AE sensor 26 as a detection device is provided, it is possible to detect the time when the grinding ability of the rotary grindstone 19 is reduced,
The direction of rotation of the rotary grindstone can be switched at an appropriate time.

(4) Since the AE sensor 26 is relatively inexpensive, the detection device can be provided at low cost. (5) Since the control device drives the rotation motor 17 in the reverse direction based on the signal sent from the AE sensor 26,
Can be automatically switched to reverse rotation.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. This embodiment uses table 2
2 and the spindle head 13 is moved left and right,
Is different from the above embodiment in that the grinding is performed not on the peripheral surface but on the end surface. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 4, a gate-shaped frame 37 is erected on the base 11. The column 12 is supported inside the frame 37 via a pair of guide rods 38 so as to be movable in the left-right direction.
4 to be moved. The guide rod 38 and the ball screw 24 pass through the upper part of the column 12.

A table 22 is provided on the base 11 so as to be movable in the front-rear direction by a moving device (not shown).
A work 25 is detachably supported on the table 22.

The rotation motor 17 is provided on the upper surface of the spindle head 13, and the rotation shaft 18 penetrates through the inside of the spindle head 13 and protrudes from the lower surface side of the spindle head 13. A rotating grindstone 19 is fixed to the lower end of the rotating shaft 18 so as to be integrally rotatable. The rotating grindstone 19 rotates forward and backward corresponding to the forward and reverse rotation of the rotation motor 17. The rotating grindstone 19 is not a peripheral surface,
The surface 25a to be ground is ground at the end surface. The AE sensor 26 is disposed on the inner wall of the frame 37 at a position facing the work 25.

At the time of grinding, first, the work 25 is fixed on the table 22. The spindle head 13 is moved up and down by the elevating motor 15, and the rotary grindstone 19 is arranged at a position where it can contact the ground surface 25 a of the work 25. Next, while the rotating grindstone 19 is rotated by the rotating motor 17,
When the column 12 is moved in the left-right direction by the moving motor 23, the rotating grindstone 19 is relatively moved in the left-right direction with respect to the work 25, and the surface to be ground 25a is ground. Next, the table 22 is moved to change the position of the surface 25a to be ground in contact with the rotary grindstone 19, and the grinding is performed in the same manner.

In the rotary grindstone 19, the abrasive grains (not shown) are worn by the forward rotation, and the swarf (not shown) accumulates on the front side in the rotation direction of the abrasive grains, so that the grinding ability is reduced. When the grinding ability is greatly reduced, the AE sensor 26 detects the sharp decrease, and the rotation is switched to the reverse rotation to continue the grinding.

According to this embodiment, the following effects are obtained in addition to the effects (1) to (5) of the first embodiment. (6) Since the end face of the rotating grindstone 19 is brought into contact with the grinding surface 25a for grinding, not only the peripheral face of the rotating grindstone 19 but also the end face can be used for grinding.

The embodiment is not limited to the above embodiment, and may be modified as follows, for example. If the position where the AE sensor 26 is disposed is near the ground surface 25a during grinding, for example, the spindle head 1
3 may be provided on the lower side or the like.

The number of AE sensors 26 is not limited to one,
A plurality may be provided. -Instead of arranging the AE sensor 26 as a detection device,
A sensor (balance vector) for detecting vibration may be provided. When this sensor is used, for example,
The abrasive grains 32 wear out during the forward rotation of
By detecting an increase in vibration when the grinding ability of the rotary grindstone 19 decreases due to accumulation of 5a, it is detected that the grinding ability has decreased.

Instead of arranging the AE sensor 26 and the balance vector as the detection device, for example, the rotation motor 17
May be provided with a sensor that detects a change in the current flowing through the sensor and detects a torque change (load torque).

The switching between the forward and reverse rotations of the rotation motor 17 is not limited to the configuration automatically performed by the control device, but may be performed manually, for example. The present invention may be applied to, for example, a rotary dresser for dressing a grindstone. That is, a rotary dresser or the like is fixed to a rotating shaft rotated by the rotating motor so as to be integrally rotatable, and the rotating motor is formed so as to be rotatable forward and backward.

In order to rotate the rotary grindstone 19 in the reverse direction, the rotation motor 17 is not limited to a motor capable of normal and reverse rotation as in the above embodiment. A gear train and a clutch for forward rotation and reverse rotation may be respectively incorporated between the rotating grindstone 19 and the rotating grindstone 19 may be reversely rotated by switching the clutch.

The technical ideas other than the claims that can be grasped from the above embodiments are described below. (1) In the invention described in claim 2, the rotating grindstone is fixed to a rotating shaft of the rotating motor.

(2) In the invention according to claim 3,
The detection device is an acoustic emission sensor (AE sensor). (3) In the invention described in claim 3, the detection device is a sensor (balance vector) for detecting vibration.

(4) In the invention described in claim 3,
The detection device is a sensor that detects a change in current flowing through the rotation motor and detects a torque change (load torque).

[0034]

As described in detail above, according to the first to third aspects of the present invention, it is possible to reduce the number of times of stopping the work of grinding the work in order to regenerate the grinding ability of the rotary grindstone.

[Brief description of the drawings]

FIG. 1 is a front view of a grinding machine.

FIG. 2 is a side view of the grinding machine.

FIG. 3 (a) is a schematic partial enlarged front view around an abrasive grain,
(B) is a schematic partial enlarged front view showing the state of reverse rotation.

FIG. 4 is a schematic front view showing a grinding machine according to a second embodiment.

FIG. 5A is a schematic partial enlarged front view showing the vicinity of an abrasive grain according to a conventional technique, and FIG. 5B is a schematic partial enlarged front view showing a sharpened state.

[Explanation of symbols]

10: grinding machine, 17: rotating motor, 18: rotating shaft, 1
9: rotating whetstone, 25: work, 25a: ground surface, 26
... AE sensor as a detecting device, 32 ... abrasive grains.

Claims (3)

[Claims] 1. A grinding machine that relatively moves along a surface to be ground of a work while rotating a rotary grindstone by a rotation motor, and grinds a surface to be ground of the work with abrasive grains contained in the rotary grindstone, At the time of grinding, first rotate the rotating grindstone in a predetermined direction,
A grinding method for a grinding machine, wherein when the grinding ability of the rotary grindstone is reduced, the rotary grindstone is rotated in the reverse direction to continue the grinding. 2. A grinding machine that relatively moves along a surface to be ground of a work while rotating a rotary grindstone by a rotation motor to grind a surface to be ground of the work with abrasive grains contained in the rotary grindstone, A grinding machine, wherein the rotating grindstone is fixed to a rotating shaft rotated by the rotating motor so as to be integrally rotatable, and the rotating motor is formed so as to be able to rotate forward and backward. 3. The grinding machine is provided with a detecting device for detecting that the grinding ability of the rotating grindstone has decreased, and the rotating grindstone after detecting that the grinding ability of the rotating grindstone has decreased by the detecting device. The grinding machine according to claim 2, wherein the grinding machine is reversely rotated.