JPH0760543A - Tapping work control device - Google Patents

Abstract

PURPOSE:To provide a tapping work control device capable of properly coping with even the case of causing worsening working accuracy and delaying working in actual cutting. CONSTITUTION:In a tapping work control device, based on a specific time constant T stored in a time constant memory circuit 4, acceleration/deceleration control of rotational speed of a main spindle and a moving speed of a Z shaft is performed by acceleration/deceleration control circuits 6, 16. In the case of performing actual cutting by this tapping work control device, it can cope with working accuracy, when worsened, by largely resetting the specific time constant T by a time constant adjusting circuit 5. The device can cope with the working time, when delayed, by small resetting the specific time constant T by the time constant adjusting circuit 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tapping machining control device, and more particularly to a tapping machining control device capable of adjusting a time constant.

[0002]

2. Description of the Related Art Conventionally, there has been a strong demand for high-speed tapping even in the case of high-speed processing. To meet the demand, for example, Japanese Patent Laid-Open No. 63-
As disclosed in Japanese Patent No. 123605, there is known a tapping processing control device that determines an acceleration / deceleration time constant from a commanded rotation speed of a spindle and performs high-speed tapping processing. According to this device, when the rotation speed of the spindle is high, the time constant is set large, so that overshoot or the like is prevented, while when it is low, the time constant is set small, so that the machining speed is increased. Planned.

[0003]

However, in the above-mentioned device, the time constant is determined only by the rotational speed of the main shaft, and therefore, when tapping such as the diameter of the tap prepared hole, the difference in cutting oil, the difference in material, etc. It was not possible to reflect the various conditions in the time constant. For this reason, in actual cutting, for example, when the diameter of the tap pilot hole is smaller than the reference, the tap is overloaded when cutting with the determined time constant, and accurate tapping is performed. I couldn't.

Further, a synchronization error between the spindle of the tapping process and the Z-axis occurs largely during acceleration / deceleration and is in inverse proportion to the time constant. Therefore, if the time constant is set too small to pursue high-speed machining, there is a problem that predetermined precision cannot be obtained due to synchronization error when high precision is required for machining. On the contrary, if the time constant is set too large in order to improve the machining accuracy, the machining will be delayed and the speed cannot be increased.

[0005] Such problems occur in many cases because the conditions of tapping are complicatedly entangled with each other, and it is almost impossible to understand until actual machining is performed. A time constant that can avoid such problems is set. It was difficult to set from the beginning. The present invention has been made in view of the above problems, and an object of the present invention is to provide a tapping processing control device that can appropriately cope with a case where a decrease in processing accuracy or a delay in processing occurs in actual cutting. To do.

[0006]

In order to solve the above problems, the invention according to claim 1 synchronizes the rotation of the main shaft and the movement of the Z axis by pulse distribution, as illustrated in FIG. 1 (A). In the tapping control device for performing tapping, the time constant storage means M11 for storing a predetermined time constant.
And a time constant adjusting means M12 for adjusting the time constant stored by the time constant storing means, and an acceleration / deceleration controlling means M13 for performing acceleration / deceleration control based on the time constant adjusted by the time constant adjusting means. The main point is that.

On the other hand, the invention according to claim 2 is shown in FIG.
In the tapping machining control device for performing the tapping machining by synchronizing the rotation of the spindle and the movement of the Z axis by pulse distribution, the time constant deciding means M21 for deciding the time constant corresponding to the rotation speed of the spindle. And a time constant adjusting means M22 for adjusting the time constant determined by the time constant determining means, and an acceleration / deceleration controlling means M23 for performing acceleration / deceleration control based on the time constant adjusted by the time constant adjusting means. The main point is that.

[0008]

In the tapping control apparatus according to the present invention having the above-mentioned structure, the acceleration / deceleration control means M13 increases or decreases the spindle rotation speed and the Z-axis movement speed based on a predetermined time constant stored in the time constant storage means M11. Performs deceleration control. On the other hand, the tapping processing control device according to claim 2 has a time constant determining means M.
Acceleration / deceleration control means M23 based on the time constant determined by 21.
The acceleration / deceleration control of the spindle rotation speed and the Z-axis movement speed is performed by.

Regardless of which tapping control device is used for actual cutting, when the machining accuracy decreases, the predetermined time constant or the determined time constant is reset to a large value by the time constant adjusting means M12, M22. It can be dealt with. Further, when the machining time is delayed, it can be dealt with by resetting the predetermined time constant or the determined time constant by the time constant adjusting means M12, M22 to a small value.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram showing a tapping processing control device according to claim 1 as a first embodiment.

The arithmetic unit 2 outputs a command value determined by the description on the machining program based on the data input from the input device 1. As the command value, the pitch P of the tap and the rotation speed S of the spindle are output. Pulse distribution circuit 3
Is the distributed pulse Ps for rotating the spindle 10 according to the pitch P of the taps and the rotation speed S of the spindle and the Z-axis 20.
It outputs a distribution pulse Pz for controlling the movement of the. Needless to say, the distribution pulses Ps and Pz are the same as the rotation of the main shaft 10 and Z.
It is calculated that the movement of the shaft 20 is synchronized with the lead of the screw to be machined.

The time constant storage circuit 4 is a circuit that stores a predetermined time constant T. In this embodiment, the time required for the spindle motor 9 to reach its maximum rotation speed is the only time constant T. I just remember. The time constant adjusting circuit 5 selects a predetermined ratio r% by the time constant adjusting code input from the input device 1 and multiplies the time constant T input from the time constant storing circuit 4 by this ratio to obtain the time constant. change,
The time constant T ′ (= T × r (%)) is output. In this embodiment, the time constant adjustment code and the ratio r% are determined by the time constant adjustment table shown in Table 1. For example, when the time constant adjustment code is M301, r = 10%, and in M310, r = 10%.
= 100% corresponds.

[0013]

[Table 1]

The acceleration / deceleration control circuit 6 of the spindle motor 9 performs acceleration / deceleration control based on the time constant T'and the distribution pulse Ps. The output pulse Qs from the acceleration / deceleration control circuit 6 of the spindle motor 9 is sent to the error counter 7 and the error counter 7
To count up. The error counter 7 is counted up by this output pulse Qs and counted down by a feedback pulse Rs described later. Therefore, the output pulse Qs and the feedback pulse R are provided inside the error counter 7.
There is a difference with s, and this is converted into an analog command signal by a DA converter not shown. This analog command signal is sent to the spindle drive circuit 8, and the spindle drive circuit 8 controls the rotation of the spindle motor 9. The main shaft motor 9 is coupled to the main shaft 10 by a gear or the like (not shown), which causes the main shaft 10 to rotate. A pulse generator 11 is connected to the main shaft 10 by direct connection or gear connection.
A feedback pulse Rs is generated according to the rotation of the. This feedback pulse Rs is output to the error counter 7 as described above. The velocity feedback loop is omitted in FIG. These form a velocity feedback loop by a known method.

On the other hand, the acceleration / deceleration control circuit 1 for the Z-axis motor 19
6 performs acceleration / deceleration control based on the time constant T ′ and the distribution pulse Pz. The output pulse Qz from the acceleration / deceleration control circuit 16 of the Z-axis motor 19 is sent to the error counter 17, and the error counter 17 is counted up. The error counter 17 is counted up by this output pulse Qz and counted down by a feedback pulse Rz described later. Therefore, there is a difference between the output pulse Qz and the feedback pulse Rz inside the error counter 17, and this is converted into an analog command signal by a DA converter (not shown).
This analog command signal is sent to the Z-axis drive circuit 18, and the Z-axis drive circuit 18 controls the rotation of the Z-axis motor 19. The Z-axis motor 19 is a gear (not shown) or the like.
, Which causes the Z-axis 20 to move. A pulse generator 21 is coupled to the Z axis 20 and generates a feedback pulse Rz according to the rotation of the Z axis motor 19. This feedback pulse Rz is output to the error counter 17 as described above. The velocity feedback loop is omitted in FIG. These form a velocity feedback loop by a known method.

Next, the function of the time constant adjusting circuit 5 will be described in detail. As shown in Table 1, the time constant adjustment code for changing the time constant of the tap in this embodiment is prepared from M301 to M310. When, for example, M301 is instructed on the machining program from the input device 1, the time constant T ′ obtained by multiplying the time constant T stored in the time constant storage circuit 4 by the ratio r (= 10%) in the tapping machining command.
Change to (= 0.1 × T). Further, for example, when M310 is instructed on the machining program, the time constant T ′ (= 1 ×) is obtained by multiplying the time constant T by the ratio r (= 100%).
Change to T). The time constant adjustment code input by the input device 1 is effectively held until the time constant adjustment code is changed. Further, in the present embodiment, the time required for the spindle 10 to reach the maximum rotation speed is the time constant T. Therefore, even if a value larger than this time constant T is set, the synchronization error and the machining accuracy will not be further improved. rare. Therefore, the ratio r selected by the time constant adjustment code is 0
It is set in the range of up to 100%.

Next, the adjustment of the time constant in actual cutting will be described with reference to the input screens during tapping shown in FIGS. 3 and 4. Initially, the programmer who creates the machining program cannot use the actual cutting conditions such as the load applied to the tap at the time of machining, and therefore the time constant T is used as it is. That is, M310 is used as the time constant adjustment code.
, And select the ratio r = 100%. This time constant T
As described above, since it is the time required for the spindle motor 9 to reach its maximum rotation speed, the machining is delayed when tapping is performed at a low speed.

FIG. 3 is an explanatory view showing an example of the input screen at this time. Here, the rotation speed S of the spindle is 1000
rpm, time constant adjustment code is M310, machining coordinate X
= 0 mm, Y = 0 mm, depth Z = -10 mm, return point Z = 2 mm, tapping processing is executed by a fixed tapping processing fixed cycle (program code G73) which is a predetermined program. is doing.

In the actual tapping process, when the tap is not overloaded, the time constant can be shortened in order to speed up the process. That is, within the range in which the tap is not overloaded due to factors such as the diameter of the tap pilot hole, the difference in cutting oil, and the difference in material, the time constant T'is set as short as possible to speed up the machining. It is preferable above. Therefore, when the tap is not overloaded during actual cutting, the programmer inputs, for example, M305 as the time constant adjustment code (see FIG. 4). That is, the time constant T ′ at this time is 0.5 × T, and therefore the time required for acceleration / deceleration is shortened compared to the previous time.

As described above, the programmer repeatedly executes the work of re-inputting the time constant adjustment code as appropriate while confirming whether or not the tap is overloaded during actual cutting. Finally, at the time when the shortest time constant T'is set within the range in which the tap is not overloaded, the program is used thereafter to maintain good accuracy for the same type of work and to shorten the time. It becomes possible to perform tapping in the processing time.

The effects obtained by the above first embodiment will be described below. That is, even when the processing is delayed in the actual cutting, it is possible to appropriately cope with it by appropriately adjusting the time constant. Specifically, when the processing time is delayed because the time constant T is too large, the ratio r is decreased to decrease the time constant T ′, thereby shortening the time required for acceleration / deceleration. The speed can be increased. Further, if the machining accuracy is lowered due to a synchronization error between the spindle and the Z-axis or an overload on the tap due to the ratio r being set too small, the machining accuracy can be increased by setting the ratio r to the contrary. Can be improved.

The functions of the arithmetic unit 2, the time constant memory circuit 4, the time constant adjusting circuit 5, the acceleration / deceleration control circuits 6 and 16 and the error counters 7 and 17 can be realized as the functions of a computer. Next, the second embodiment will be described. FIG. 5 is a schematic configuration diagram showing a tapping processing control device according to claim 2 as a second embodiment.

The configuration of the second embodiment is the same as that of the first embodiment except that the time constant determination circuit 14 is provided in place of the time constant storage circuit 4 of the first embodiment, and therefore the same configuration. The same symbols are attached to the elements and the description thereof is omitted. As shown in Table 2, the time constant determining circuit 14 includes a time constant table which is a correspondence table of the time constant T corresponding to the rotation speed S of the spindle in this embodiment, and the rotation speed S of the spindle is commanded. Then, the time constant T corresponding to this is selected. still,
Instead of providing the time constant table as shown in Table 2, the time constant T may be calculated by the equation T = KS (K is a constant).

[0024]

[Table 2]

The time constant adjusting circuit 15 is the same as that of the first embodiment except that the time constant adjusting table shown in Table 3 is used. That is, the time constant adjustment table of this embodiment is M
301 to M319 are prepared. For example, when the time constant adjustment code is M301, r = 10%, and in M310, r = 1.
For 00% and M319, r = 190% corresponds.

[0026]

[Table 3]

Next, the function of the time constant adjusting circuit 15 will be described in detail. As shown in Table 3, the time constant adjustment code for changing the time constant of the tap in this embodiment is M
It is prepared from 301 to M319. For example, when M301 is instructed on the machining program from the input device 1,
Time constant determining circuit 1 for time constant in tapping processing instruction
The time constant T determined by 4 is multiplied by a ratio r (= 10%) to change to a time constant T '. Further, for example, when M319 is instructed on the machining program, the time constant is also changed to the time constant T ′ obtained by multiplying the time constant T by the ratio r (= 190%). The time constant adjustment code input by the input device 1 is effectively held until the time constant adjustment code is changed.

Next, the time constant in actual cutting can be adjusted in the same manner as in the first embodiment. Therefore, the description thereof is omitted. The effects obtained by the second embodiment will be described below. That is, even when the processing is delayed or the processing accuracy is lowered in actual cutting, it is possible to appropriately deal with the problem by appropriately adjusting the time constant. Specifically, when machining is delayed because the time constant T is too large, the ratio r is reduced to reduce the time constant T ′ to shorten the time required for acceleration / deceleration. The speed can be increased. Further, when the time constant T is too small, the synchronization error between the spindle and the Z axis becomes large, or the tapping is overloaded, resulting in a decrease in machining accuracy. By increasing T ', the processing accuracy can be improved.

Further, in the second embodiment, the time constant determining circuit 14
Since the time constant T is determined according to the rotation speed of the main shaft, there is less risk of overshoot at high speed and delay of machining at low speed, as compared with the first embodiment. Needless to say, the present invention is not limited to the above embodiments, and can be implemented in various modes without departing from the scope of the present invention.

For example, in the first embodiment, the time constant T is defined as the time constant T which is the time required for the spindle motor 9 to reach its maximum rotation speed or the time required for the Z-axis motor 19 to reach its maximum rotation speed. You may store only one. According to this time constant T, there is an advantage that neither the spindle motor 9 nor the Z-axis motor 19 is overloaded.

[0031]

As is apparent from the above description,
According to the tapping processing control device of the present invention, even when a decrease in processing accuracy or a delay in processing occurs in actual cutting,
It is possible to take appropriate measures by adjusting the time constant as appropriate.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a basic configuration of a tapping processing control device of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of the first embodiment.

FIG. 3 is an explanatory diagram showing an input screen of a machining program of the first embodiment.

FIG. 4 is an explanatory diagram showing an input screen of a machining program of the first embodiment.

FIG. 5 is a block diagram showing an electrical configuration of a second embodiment.

[Explanation of symbols]

1 ... Input device, 2 ... Calculator, 3 ... Pulse distribution circuit, 4 ...
..Time constant storage circuits, 5, 15 ... Time constant adjustment circuits,
6, 16 ... Acceleration / deceleration control circuit, 7, 17 ...
..Error counter, 8 ... Spindle drive circuit, 9 ... Spindle motor, 10
... Spindle 11,21 ... Pulse generator,
14 ... Time constant determination circuit, 18 ... Z-axis drive circuit, 19 ... Z-axis motor, 20 ...
Z axis,

Claims (2)

[Claims] 1. A tapping machining control apparatus for performing tapping machining by synchronizing rotation of a spindle with movement of a Z axis by pulse distribution, and a time constant storage means for storing a predetermined time constant, and the time constant storage means. A tapping processing control device comprising: a time constant adjusting means for adjusting the stored time constant; and an acceleration / deceleration controlling means for performing acceleration / deceleration control based on the time constant adjusted by the time constant adjusting means. . 2. A tapping machining control apparatus for performing tapping machining by synchronizing rotation of a spindle with movement of a Z-axis by pulse distribution, and a time constant determining means for determining a time constant corresponding to a rotation speed of the spindle. A time constant adjusting unit that adjusts the time constant determined by the time constant determining unit; and an acceleration / deceleration control unit that performs acceleration / deceleration control based on the time constant adjusted by the time constant adjusting unit. Tapping processing control device.