JPH0516067A - Control method and device for automatic grinding in grinder - Google Patents

Abstract

PURPOSE:To solve a problem caused by automatic grinding by means of a conventional grinder; namely, an expensive NC(numerically controlled) device is necessary for the automatic grinding, and expensive machine elements such as a servomotor, ball screws requiring high accuracy are used to use the NC device, thereby increasing the total cost of the grinder. CONSTITUTION:In a surface grinder 1, when it is detected that a periphery of a grinding wheel 15, which is provided on a grinding wheel spindle 11 with the grinding wheel 15, is in contact with a work W, a vertical movement driving device 47 of the grinding wheel spindle 11 is stopped, and a driving device 57 of a micro-feed gear 23 is operated, so that cutting is conducted to the work finishing position at the previous cycle, which is set to a first counter 63. Next, according to a second counter 65, to which an abrasion amount of the grinding wheel 15 during one cycle is set, a driving device 57 of the micro-feed gear 23 is operated in order to conduct the cutting to the prescribed depth, thereby correcting the abrasion amount of the grinding wheel 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic grinding control method and apparatus for a grinding machine, and more particularly to an automatic grinding control for a grinding machine in which the amount of wear of a grindstone in one cycle is corrected and controlled in the next cycle. A method and an apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, when a grinder is used to automatically approach a workpiece to a grindstone, grind to a set size, retract a grindstone shaft, and perform automatic grinding to grind a large number of workpieces of the same type continuously. In the case of, the grindstone wears, and it is not possible to control the finish dimension of the work.

For this reason, automatic grinding is performed by a method in which the wear amount of a grindstone is input as a correction value using an NC device, and a large amount of the correction value is cut during grinding to obtain the size of a work.

[0004]

By the way, in the case of automatic grinding with the above-mentioned conventional grinder, an expensive NC device is used, and as a device for using the NC device, a servomotor, a ball screw is used. As a result, there is a problem in that a highly accurate and expensive machine element must be used and the total cost of the grinder becomes high.

In order to improve the above problems, an object of the present invention is to add a grindstone wear amount correction means to a general-purpose grinder which is not equipped with an NC device to a manual grinder to enable automatic grinding, An object of the present invention is to provide an automatic grinding control method and apparatus for a grinding machine, which improves operability and productivity.

[0006]

In order to achieve the above object, the present invention provides a motor drive device for rotationally driving a grindstone shaft provided with a grindstone for grinding a workpiece mounted on a table, and the grindstone shaft. In a grinding machine equipped with a vertical movement motor drive device that moves up and down via a transmission member and a fine feed device on the input shaft of the transmission member that moves the grinding stone shaft up and down, the outer circumference of the grinding stone provided on the grinding stone shaft contacts the workpiece. It is detected that the motor drive device for vertical movement of the grindstone shaft is stopped, and the drive device of the minute feed device is activated to make a cut to the work finishing position set in the first counter at the time of the previous cycle, and then 1 cycle. Grinding in which the amount of wear of the grindstone is corrected by operating the drive unit of the micro-feeding device by the second counter in which the amount of wear of the grindstone is set An automatic grinding control method in a.

Further, according to the present invention, there is provided a motor drive device having a minute current measuring device for rotationally driving a grindstone shaft equipped with a grindstone for grinding a work mounted on a table, and the grindstone shaft via a transmission member. A vertical movement motor drive device that moves up and down and a fine feed device provided on the input shaft of the transmission member that moves the grindstone shaft up and down, and the amount of wear of the drive device that operates this fine feed device in one cycle of the grindstone is set. The automatic grinding control device in the grinder is provided with a first counter that controls the motor drive device for vertical movement of the transmission member and the position detector that is provided on the input shaft of the transmission member while controlling by the second counter. Configured.

[0008]

By adopting the automatic grinding control method and apparatus for the grinding machine of the present invention, a fine feed device is provided on the input shaft of the transmission member for moving the grindstone shaft up and down, and a drive device for operating the fine feed device is provided. , A second counter that sets the amount of wear of the grindstone in one cycle is controlled. Also,
A vertical movement motor drive device that drives the transmission member and a first counter that controls a position detector provided on the input shaft of the transmission member are provided.

Therefore, it is detected that the outer circumference of the grindstone provided on the grindstone shaft is in contact with the work, the motor drive device for the vertical movement of the grindstone shaft is stopped, and the drive device of the minute feed device is operated, so that the first Make a cut to the work finish position of the previous cycle provided on the counter. Subsequently, the wear amount of the grindstone can be corrected by operating the drive unit of the micro-feed device to make a predetermined amount of cut by the second counter in which the amount of wear of the grindstone in one cycle is set.

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings. As the grinder, a general-purpose surface grinder will be described as an example, but the grinder is not limited to this.

Referring to FIG. 3 and FIG. 4, the surface grinder 1 will be briefly described because it has a known structure.
The surface grinder 1 is provided with a table bed 5 on a base 3. Although not shown, the table bed 5 is provided with a table 7 that reciprocates in the X-axis direction (the horizontal direction in FIG. 3 and the direction orthogonal to the drawing in FIG. 4) by an electric motor or a cylinder operated by fluid pressure. ing. Further, the table 7 is movable in the Y-axis direction (direction orthogonal to the drawing in FIG. 3, left-right direction in FIG. 4).

Although not shown, a chuck or a jig for gripping the work is mounted on the table 7, and the work is moved in the X-axis and Y-axis directions.

On the other hand, the rear side of the base 3 (right side in FIG. 4)
A column 9 is erected on the column 9, and the grindstone shaft 1 is movable on the column 9 in the Z-axis direction (vertical direction in FIGS. 3 and 4).
1 is provided, the grindstone shaft 11 is rotated by the motor drive device 13, and the grindstone 15 is provided at the tip of the grindstone shaft 11.

With the above construction, the work is clamped on the table 7 by a chuck or the like, the table 7 is reciprocated in the X-axis direction and moved in the Y-axis direction, and the grindstone 15 is rotated by the drive of the motor drive device 13. The grinding process is performed by moving the grindstone shaft 11 downward in the Z-axis direction and cutting the workpiece.

The vertical feed mechanism of the grindstone shaft 11 installed in the column 9 will be described in more detail.

Referring to FIG. 1, the vertical feed mechanism 17 of the grindstone shaft 11 includes a wheel head 19 equipped with the grindstone shaft 11.
And a transmission member 2 for moving the wheel head 19 up and down
1, and a minute feeding device 23 provided on the transmission member 21,
It is composed of a controller 25 for controlling each driving device.

The wheel head 19 has a known structure and is installed in the column 9 so as to be movable up and down.
A grindstone shaft 11 is rotatably mounted on the wheel head 19, the grindstone shaft 11 is rotatable by a motor drive device 13, and a grindstone 15 is mounted on the tip of the grindstone shaft 11.

With the above structure, the grindstone shaft 11 is rotated by driving the motor driving device 13, and the grindstone 15 provided on the grindstone shaft 11 is rotated.

The transmission member 21 for moving the wheel head 19 up and down is provided with an input shaft 27 extending in the Y-axis direction in parallel with the grindstone shaft 11. The tip of the input shaft 27 is manually operable. A handle 29 is integrally provided. A worm 31 is threaded near the center of the input shaft 27,
A worm wheel 33 is screwed onto the worm 31, and the worm wheel 33 is integrally provided with a nut member 37 screwed onto a vertical feed screw 35 hanging from the wheel head 19.

A pair of gear transmissions 39 are provided on the side opposite to the handle of the input shaft 27.
The output side gear 41 is fixed to the input shaft 27, and the input side gear 43 meshing with the output side gear 41 is connected via a clutch 45 to a vertical movement motor drive device 47 such as a geared motor. Further, at the shaft end of the input shaft 27, a position detector 49, for example, an encoder is provided. It is also possible to interpose a clutch between the handle 29 and the input shaft 27 to make the rotation of the handle 29 free with respect to the input shaft 27.

With the above structure, by driving the vertical movement motor drive device 47, the rotation is transmitted to the input side gear 43 via the clutch 45, and the output side gear 41 meshing with the input side gear 43 rotates to rotate the worm 31. And the worm wheel 33 meshing with the worm 31 rotates. Nut member 37 built in the worm wheel 33
As the vertical feed screw 35 moves up and down via the wheel head 19, the wheel head 19 moves up and down. Also, the transmission member 2
When operating 1 manually, the wheel head 19 can be moved up and down by disengaging the clutch 45 and operating the handle 29.

The minute feed device 23 is provided on the input shaft 27 of the transmission member 21 and has a ratchet type structure. Since it is already known, detailed description thereof will be omitted.

Ratchet wheel 5 provided on the input shaft 27
The claw portion 55 of the claw member 53 meshes with the claw member 1, and the claw member 53 is connected to a drive device 57, for example, a fluid pressure cylinder. The engaging direction of the claw portion 55 of the claw member 53 meshes in the direction in which the wheel head 19 descends, and when the wheel head 19 rises, the claw portion 55 and the ratchet wheel 51 are free. The claw member 5
The driving device 57 for activating 3 is operated via a solenoid switching valve 59 from a fluid pressure generation source (not shown).

With the above structure, a cylinder, which is the drive unit 57, is actuated from a fluid pressure generation source (not shown) via the electromagnetic switching valve 59, and the claw portion 55 of the claw member 53 engages with the ratchet wheel 51 (see the figure). By moving from 1 left side to 1 right side in 1), the ratchet wheel 51 is rotated by a predetermined amount in one stroke. Ratchet wheel 5
1 rotation causes the worm 31, the worm wheel 33,
The wheel head 19 is lowered by a predetermined amount via the nut member 37 and the vertical feed screw 35, and the grindstone 15 can cut the work by a predetermined amount. In addition, the electromagnetic switching valve 59
By turning on and off, the oil passages T and P are switched, and the drive device 57 moves forward and backward. Therefore, it is possible to rotate the input shaft 27 stepwise and perform cutting and grinding by a minute amount.

Next, a controller 25 for controlling each driving device
Is a motor driving device 13 for driving the grindstone shaft 11 provided on the wheel head 19, for example, a minute current measuring device 61 for detecting a load of a spindle motor. This minute current measuring device 61 senses the load applied to the grindstone 15,
A stop signal is output to the geared motor of the vertical movement motor drive device 47 that rotates the vertical feed screw 35.

A position detector 49 provided on the input shaft 27
The encoder is provided with a first counter 63 (for example, a two-stage preset counter) that counts pulse signals. The first counter 63 outputs a stop signal to the geared motor of the vertical movement motor drive device 47 that drives the input shaft 27, and also outputs a stop signal to the electromagnetic switching valve 59 that operates the drive device 57 of the fine feed device 23. It is configured to do.

Further, a second counter 65 for controlling the electromagnetic switching valve 57 is provided. This second counter 65
Can freely set the number of times the cylinder of the drive unit 57 is activated.

With the above-mentioned structure, the operation will be described in detail step by step with reference to FIG.

First, a girder motor, which is a vertical motor drive device 47, is driven to lower the grindstone shaft 11.
(Step S-1) When the lower surface of the outer periphery of the grindstone 15 rotatably provided together with the grindstone shaft 11 comes into contact with the workpiece material position (indicated by the line WW in FIG. 2), the grindstone 15 is attached to the grindstone 15 by the minute current measuring device 61. When the applied load is sensed, the geared motor, which is the vertical motor drive device 47, is stopped. (Step S-2) Then, at the same time when the geared motor, which is the vertical movement motor drive device 47, is stopped, the cylinder, which is the drive device 57 of the minute feed device 23, is operated to perform the cut grinding on the work. (Step S-3) As the grinding work progresses, the workpiece finish position at the previous cycle (indicated by the PP line in FIG. 2), that is, the first counter 63 attached to the encoder that is the position detector 49 is used. Grinding work is continued up to the position where NO1 of a certain two-stage preset counter was automatically reset in the previous cycle. (Step S-4) When the workpiece finish position PP has been ground, the second counter 65 is operated, and the fine feed device 23 is operated the number of times set in the second counter 65 to perform the grinding cut. . Then, the grinding operation is finished at the position where the set number of cuts have been completed (shown by the line Q-Q in FIG. 2). (Step S-5) Depth of Cut K from Step S-4 to Step S-5
Is the amount of abrasion of the grindstone 15 in one cycle, and this amount is set in the second counter 65. At the position indicated by the line Q-Q, the NO1 counter of the two-stage preset counter, which is the first counter 63, is set to auto 0 reset.

The grinding process is completed as described above, and then the grindstone 15
Move to the ascending process. That is, the numerical value set to NO2 of the two-stage preset counter which is the first counter 63 is the sum of the grinding amount of the work and the maximum value of the variation amount of the material thickness, that is, the retract amount. The counter 63 of No. 1 operates the geared motor of the vertical movement motor drive device 47 to raise the grindstone 15. (Step S-6) The wear amount of the grindstone 15 can be corrected and automatically controlled by controlling each device in the cycle as described above.

For this reason, an expensive NC device is not required, additional modifications can be made to a general-purpose machine, and it is possible to provide a highly accurate machine at a low cost. Further, by adding it to a general-purpose machine, it is possible to improve the operability and reduce the man-hours of the worker, and it is possible to improve the productivity.

The present invention is not limited to the above-described embodiments, but can be implemented in other modes by making appropriate changes. For example, in the present embodiment, the movement of the wheel head 19 is controlled, but a method of controlling the vertical movement of the table 7 is also possible.

The contact detection between the grindstone 15 and the workpiece is AE.
A sensor or the like is also possible, and the encoder has been described as the position detector 49, but a magnescale or the like may be adopted. Further, although the ratchet mechanism is adopted as the minute feed device 23, a rotary actuator or the like may be used, and the position detector 49, the vertical movement motor drive device 47, the clutch 45 and the like can be attached to the tip of the vertical feed screw 35.

[0034]

As will be understood from the above description of the embodiments, according to the present invention, when it is detected that a workpiece is in contact with the outer periphery of the grindstone, the vertical motor drive device for moving the grindstone shaft up and down is stopped. At the same time, the fine feed device is operated to perform cutting to the work cutting position set in the first counter in the previous cycle. Then, with a second counter that sets the amount of wear of the grindstone in one cycle,
Operate the minute feed device to make a predetermined amount of cut.

Therefore, since the amount of wear of the grindstone is controlled for each cycle to perform the cut grinding, the grinding can be performed with high accuracy. In addition, a general-purpose machine, a manual machine, or the like can be additionally modified without using an expensive NC device, which can reduce the total cost of the grinder and improve operability and productivity.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view showing a main part of the present invention and showing an outline of a grindstone shaft vertical feed mechanism.

FIG. 2 is an operation explanatory view of FIG.

FIG. 3 is a front view of a surface grinder of an embodiment for carrying out the present invention.

FIG. 4 is a side view of FIG.

[Explanation of symbols]

1 surface grinder 7 table 11 Wheel axis 13 Motor drive 15 whetstone 21 Transmission member 23 Fine feed device 27 Input axis 47 Vertical movement motor drive device 49 Position detector 57 Drive 61 Micro current measuring instrument 63 First Counter 65 Second Counter

Claims (2)

[Claims] 1. A motor drive device for rotationally driving a grindstone shaft provided with a grindstone for grinding a workpiece mounted on a table, and a vertical motor drive device for vertically moving the grindstone shaft via a transmission member. In a grinding machine equipped with a fine feed device on an input shaft of a transmission member for moving the grindstone shaft up and down, it is detected that the outer circumference of the grindstone provided on the grindstone shaft comes into contact with the work, and the motor drive device for vertical movement of the grindstone shaft is stopped. At the same time, the drive device of the fine feed device is operated to make a cut to the work finish position in the previous cycle set in the first counter, and then the second counter that sets the amount of abrasion of the grindstone in one cycle is set An automatic grinding control method in a grinding machine, characterized in that a drive device of a feeding device is operated to perform a predetermined amount of cutting to correct a wear amount of a grindstone. 2. A motor drive device equipped with a minute current measuring device for rotationally driving a grindstone shaft equipped with a grindstone for grinding a workpiece mounted on a table, and the grindstone shaft is moved up and down via a transmission member. A vertical movement motor drive device and a fine feed device are provided on an input shaft of a transmission member for moving the grindstone shaft up and down, and a drive device for operating the fine feed device is set to a second amount in which the amount of wear of the grindstone in one cycle is set. An automatic grinding control in a grinding machine, which is controlled by a counter and further includes a first counter for controlling a vertical drive motor driving device for the transmission member and a position detector provided on an input shaft of the transmission member. apparatus.