JPS58186561A - Numerical controller - Google Patents

Abstract

PURPOSE:To shorten the time of a machining cycle, by distributing pulses for a control axis from the time when numerical control is executed up to a prescribed step in the distribution of pulses for another control axis. CONSTITUTION:After a pulse distribution speed for moving a grinding wheel G back and a first number of distributed pulses are set in a pulse generation circuit 13a and pulse distribution for an axis X is started, a pulse distribution speed for moving a grindstone correcting tool DT rapidly and a first number of distributed pulses are set in a pulse generation circuit 13b so that the backward movement of the grinding wheel and pulse distribution for an axis U is started so that the backward movement of the grinding wheel and the rapid forward movement of the grindstone correcting tool are simultaneously begun. The pulse generation circuits 13a, 13b differ from each other in the time cost until the completion of the pulse distribution, so that pulse distribution compeltion signals are sent out at different times. The pulse distribution is effected in a time division manner for the axes X, U alternately.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a numerical control device that controls the operation of a machine tool by distributing pulses to a plurality of control axes according to control data of a predetermined number M. The purpose of this is to simultaneously distribute pulses to the main control axis that controls the movement of processing tools, etc. according to the main numerical control program. It is possible to perform processes such as simultaneously executing pulse distribution for the main control axis independently and simultaneously with Nockles distribution for the main control axis, and it is possible to start other operations unrelated to the movement of the processing tool from a position in the middle of the movement process of the processing tool. It is to make it.

In recent numerically controlled grinding machines, it is necessary to control not only the forward and backward movement of the grinding wheel relative to the workpiece, but also the forward and backward movement of the grinding wheel correction tool relative to the grinding wheel, indexing of the workpiece table, feeding of the rest device, etc. However, with conventional numerical control devices, it is not possible to advance and retreat the grinding wheel and perform other operations in parallel, which is one reason why it is not possible to shorten the machining cycle time. was.

In other words, if we take the movement of the correction tool for the grinding wheel correction as an example, although this movement cannot be performed during machining, the feeding starts immediately after the grinding wheel starts moving backwards, and the grinding wheel moves during the backward movement of the grinding wheel. It is possible to correct the wheel, and in this way, by the time the grinding wheel returns to the backward end, the grinding wheel correction has been completed and the subsequent machining can be started directly. Processing cycle time can be shortened.

However, in conventional numerical control devices, although it is possible to simultaneously distribute pulses to multiple axes such as linear interpolation where the start and end times of movement are the same, Since it is impossible to perform pulse distribution at the same time at all, as described above, the processing cycle is performed by distributing pulses to move the grinding wheel correction tool forward and backward to and from the grinding wheel correction wheel in parallel with the pulse distribution to move the grinding wheel backward. I couldn't shorten the time.

The present invention has been made in view of these conventional problems, and includes storing in a storage means a plurality of numerical control data programmed corresponding to each of a plurality of control axes that need to be operated independently. At the same time, each axis muscle is provided with a pulse generation circuit capable of independently distributing pulses, and when a start command is given, one numerical control of the plurality of numerical control data stored in the storage means is provided. Performs pulse distribution only based on data, and in response to this one numerical control data being executed in a predetermined step 1, pulse distribution based on this one numerical control data and simultaneously pulse distribution based on other numerical control data. This is characterized in that pulse distribution is performed in parallel.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, reference numeral 10 controls the forward and backward movement of the grinding wheel G with respect to the workpiece W to perform numerical control processing on the workpiece W, and also controls the forward and backward movement of the grinding wheel correction tool DT with respect to the grinding wheel G. This is a numerical control device that performs corrections by numerical control, and is mainly composed of an arithmetic processing device 11, a memo 1J12, and pulse generation circuits 13a and 131). Then, the arithmetic processing unit 11 receives 7'tll! The Durham writing device 15 and the sequence IIJ controller M16 are connected via a circuit interface.

The program writing device 15 writes the numerical control program for machining the workpiece shown in FIG. 2(a) and the numerical control program for grinding wheel correction shown in FIG. 2(b) prior to machining the workpiece. The written numerical control program is stored in the main program area MPA and subprogram area SPA in the memory 12, respectively. The numerical control program for machining the workpiece moves the grinding wheel G rapidly forward by a distance Do, and then moves the grinding wheel G forward by a distance D1 at a rough grinding feed rate F1.
Fine grinding The workpiece W is advanced by a distance D2 at a feed rate F2.
After that, the grinding wheel G is returned to the backward end by fast forwarding backward by a distance D3, and the numerical control data for commanding the backward movement of the grinding wheel G is programmed in the block N0O3 before the block N004. is programmed with an auxiliary function code MO3 that commands the start of grindstone correction.

In addition, the program for grinding wheel correction is the grinding wheel correction tool D.
Since T is a rotary type, the grinding wheel correction tool DT is moved forward by a distance D5 in rapid traverse, then the grinding wheel correction is completed by moving it forward by a distance D6 at a speed of F3, and after this, the correction tool DT is returned by a distance D5. , the grinding wheel G is advanced by a distance D6 to compensate for the decrease in the diameter of the grinding wheel G due to the grinding wheel correction.

On the other hand, the pulse generation circuits 13a and 13b send pulses to the drive units DUX and DUU, which drive the servo motor 17 for advancing and retracting the grinding wheel G and the servo motor 18 for advancing and retracting the correction tool DT, respectively, according to instructions from the processing unit 11. This is the pulse generation circuit 13a.

13b has a speed register 20 a + 20 b s for setting the pulse period.
an oscillator 21a that generates pulses at a rate set in a, 20b;

21b, the output from this oscillator 21a, 21b is positive,
Gate circuits 23a, 23 that distribute as negative pulses
b.

It is composed of preset counters 22a and 22b which calculate the pulses output from the oscillators 21a and 21b and output pulse distribution completion signals DKNX and DENU when the counted value becomes equal to the preset value. The arithmetic processing device 11 includes a pulse generation circuit 13a.

Every time the pulse distribution completion signals DENX, DENU are output from the preset counters 22a, 22b in the preset counters 22a, 22b in the preset counters 22a, 22b, a new movement amount is output as the pulse distribution completion signals DENX, D.
Continuous pulse distribution is performed by setting the preset counter 22a or 22bvC to which KII is sent.

Furthermore, the sequence control circuit 16 has a circuit configuration shown in FIG. 3, and when the start button 5TART is pressed, the relay C! for machining cycle command is pressed! The RIO is turned on and instructs the numerical control device 10 to start executing the machining program shown in FIG. 2(a), which is the main program. If the auxiliary function code MO3 is read out during the execution of this program, the code MO3 is output from the numerical control device 10 to the sequence control circuit 16, and when the contact m03 is closed in response, the grinding wheel is corrected. The cycle command relay 0R20 is turned on and commands the numerical control device 10 to start executing the subprogram, the grindstone correction program shown in FIG. 2(b).

As mentioned above, the auxiliary function code MO3, which commands the start of grinding wheel correction, is programmed before the grinding wheel retraction command, so as shown in FIG. Operations are performed in parallel.

Next, the operation of the numerical control device 10, particularly the process of simultaneously performing the backward movement of the grinding wheel G and the correction operation of the grinding wheel G will be explained.

When the operation is started, the arithmetic processing unit 11 in the numerical control device 10 executes the program shown in FIG. Of this program, the program in steps (31) to (43) executes the numerical control program for machining stored in the main program area MPA of the memory 12, and the program in steps (51) to (43)
) to (63) are for executing the grinding wheel correction program stored in the subprogram area SPA of the memory 12, and in step (30), the relay 0RIO of the sequence control circuit 6 is turned on. If it is determined that a grindstone correction command has been sent in step (31) to step (43), the program in steps (31) to (43) is executed.If relay 0R20 of the sequence control circuit 16 is still on, step ( 31) to C43), the process moves from step (30) or step (33) to step (51) via step (50), and continues. Step (51) to step (63)
By executing the program , processing for executing the grindstone correction program in the subprogram area SPA is performed.

Programs and steps of steps (31) to (43) (
The processing contents of the programs in steps 51) to (63) are almost the same, and in the programs in steps (31) to (43), the numerical control data of the block specified by the main program counter MPC is read out from the main program area MPA and executed. On the other hand, in the program of steps (51) to (63), the numerical control data of the block specified by the subprogram counter SPC is transferred to the subprogram area S.
The only difference is that it is read from the PA and executed. Note that the main program counter MPC and sub-program counter SPC are formed in predetermined areas within the memory 12.

Now, start switch 5TART of sequence control circuit 16
is pressed, relay 0RIO turns on, and numerical control device 1
0, the arithmetic processing unit 11 of the numerical control device 10 executes step (30
) detects this, and in step (32) executes initialization processing to reset the main program counter MPC to zero. After this, the process moves to step (35) via step (33), and the numerical control data Goo Xll0 of the block NQOQ specified by the main program counter MPC is read.
6), it is determined whether or not the X-axis, which is the pulse distribution axis, is currently distributing pulses using the interlock table error RT described later.
If it is not being distributed, proceed to step (37).
) The subsequent program performs processing according to the numerical control data.

In this case, since the numerical control data includes the G code, the process moves from step (37) to step (37a) and processing according to the G code is performed. The process moves to step (41) via L steps (3B) and (40), and pulse distribution processing is performed. The processing of pulse distribution of the motor is performed in step (41) by setting the data of the movement amount D1 in the movement amount counter When information indicating that the X-axis pulse distribution has started is written in the interlock table area RT formed in a predetermined area of the memory 12, the counter MPO is advanced, and after this, the pulse distribution shown in FIG. Routine P
The process moves to step (70) of GH, and the pulse distribution routine is run through once. Note that by running one pulse distribution routine at the same time, pulse distribution toward the X axis is started.
The subsequent pulse distribution processing is performed only by the pulse distribution routine.

That is, when the process starts from step [70] of the pulse distribution routine, first, in step (70), one of the pulse distribution completion flags DEFX and DEFU provided for the X and U axes, which corresponds to the movement axis, is selected. The X-axis pulse distribution completion flag DEFX is reset, and then the data representing the moving direction is sent to the X-axis pulse generation circuit 1.
3a Output K to switch gates. After this, it is determined whether pulse distribution to the X-axis has been completed based on whether the count value of the X-axis movement amount counter XPTOTL is zero, and if pulse distribution has not been completed, , moving from step (73) to (77), speed data and
Data representing the number of pulse distribution for one time is outputted to the pulse generating circuit 13a, a pulse distribution start command is outputted, and thereafter, the pulse distribution number is decreased from the moving amount counter XPTOTL to the base routine.

As a result, the pulse generation circuit 13a distributes a set number of pulses to the X-axis at a designated speed, and when this is completed, it sends a distribution completion signal DENX to the arithmetic processing unit 11. As a result, the arithmetic processing unit 11 starts executing the pulse distribution routine from step (72) shown in FIG.
First, after determining the pulse distribution axis based on which noggle generation circuit has sent out the distribution completion signal,
The process moves to step (73), where the same process as in the previous case is performed, and when this process is completed, the process returns to the base routine. Thereafter, by repeating the same operation, pulse distribution to the X axis is continued, and the grinding wheel G is moved forward in rapid traverse.

Note that even during the noguru distribution operation by this pulse distribution routine, the program shown in FIG. 5(a) is executed at regular intervals in synchronization with the interrupt signal from the RTO circuit 25, has not been completed, relay 0R20 remains off, and no grinding wheel correction command is given to the numerical control device 10, so the process returns to the pace routine from step (33) to step (50). However, no substantive processing is performed.

When the number of pulses corresponding to the movement amount Dl commanded by the above operation is distributed and the contents of the movement amount counter XPTOTL become zero, that is, when the rapid advance of the grinding wheel G is completed, in step (75) The data indicating that the X-axis pulse distribution is in progress is erased from the interlock table RT, and the X-axis pulse distribution completion flag is set in step (76).
When the routine is executed, step C33)
It is determined that the shaft nogle distribution is complete.

Then, the process moves from step (33) to step (35), and the processing of steps (33) to (43) is performed again, and the numerical control data GOIXD engineering F engineering programmed in block N0OL of the machine program which is the main program is is read out, and the noggles are distributed on the X-axis in the same manner as described above, and the grinding wheel G is fed for rough grinding. Then, when the programmed GOI
The data of MO3 programmed in O3 is read out, and in step (38a), a process is performed to send the code of MO3 to the controller 16. Then, after returning to the base routine, the process shown in FIG. 5(a) is executed again, and in step (35), the program for reversing the grinding wheel G programmed in block BJQO4 -D3 F3 is read out and pulse distribution for grinding wheel G retraction is started. As mentioned above, since the program shown in FIG. The process starts from the moment the signal is sent and is completed by the time the next signal is sent.

On the other hand, when the M2S code is sent to the sequence control circuit 16, the relay 0R20 is energized, and when the numerical control circuit is activated,
As shown in FIG. 7, the arithmetic processing unit 11 executed the program shown in FIG. 5(a) in response to the signal L sent from the RTCl path 25 immediately after the X-axis pulse distribution was performed. At the same time, the process moves to step (33) and step (50), and this is detected in step (50), and as shown in FIG.
) The subprogram execution processing after step (51) shown in ) is performed.As a result, first, the program of the numerical control data Goo UD5 for the correction tool rapid forward movement programmed in the first block N100 of the subprogram is read out, After this, in step (56), it is determined whether or not pulse distribution is currently being performed for the U-axis by referring to the interlock table RT, and if pulse distribution is not being performed for the U-axis. , the process moves to step (57) and subsequent steps to perform pulse distribution processing.In this case, since pulse distribution to the U-axis is not performed, the process moves from step (56) to step (57), and then processes step (57). '7a) After performing vc and G code processing, in step [61] the U-axis movement amount D5 is set in the U#I movement amount counter UPTOTL, and further, in step (62), the U-axis movement amount D5 is set in the interlock table ERT. At the same time as writing the data during axis movement, in step (63) the subprogram counter SPA is incremented by a full step and the process moves to the pulse distribution routine.

As a result, the pulse distribution speed and the initial distribution pulse number for grinding wheel retraction are set in the pulse generation circuit 13a, and
After the pulse distribution to the axis is started, the pulse distribution speed and the initial distribution pulse number for rapid feed of the grindstone correction tool are set in the pulse generation circuit 13b, and the pulse distribution to the U axis is started.

As a result, the backward movement of the grinding wheel G and the rapid mT movement of the grinding wheel correction tool DT are started simultaneously.

Then, when the number of pulses set in the pulse distribution circuits 13a and 13b are distributed to the X axis and the U axis, respectively, a distribution completion signal DENX is sent from the pulse generation circuits 13a and 13b.
, DEIJU are sent, and in response the Noculus distribution routine described above is executed again. Since the feed speeds of both axes are normally the same, the time required for the pulse generating circuits 13a and 13b to complete pulse distribution is different, and therefore, the pulse distribution completion signal DENX is usually the same.

The DENU is sent out at different times, and the pulse distribution routine alternately processes pulse distribution for the X-axis and pulse distribution for the U-axis in a time-sharing manner.

Although it is omitted in the flowchart, if pulse distribution completion signals are sent from both pulse generation circuits 13a and 13b at the same time, pulse distribution processing for the X-axis is performed first, and then pulse distribution processing for the U-axis is performed. It is supposed to be done.

By repeating such processing, the backward movement of the grinding wheel G is controlled, and subprograms for grinding wheel correction are read in order, and the grinding wheel correction tool 1) is read out in order.
In order to correct the grinding wheel, T performs pulse distribution of rapid forward forward movement, forward cutting forward, and rapid backward movement, and when this is completed, the grinding wheel position correction program GOOXD6 programmed in block N103 of the subprogram is read out. , pulse distribution to the X axis is performed based on the subprograms. However, as shown in FIG. 4, if the retraction of the grinding wheel G is not completed at this point and the pulse distribution to the X axis continues, the interlock table error RTI/i:X Since data indicating that the axis is undergoing pulse distribution is written, this is determined in step (56) of the subprogram execution routine, and no processing is performed until the X-axis pulse distribution is completed. Return to the base routine without performing any operations. As a result, the pulse distribution process based on the subprogram is interrupted until the retraction process of the grinding wheel G based on the main program is completed.
The grinding wheel G has retreated to the backward end, the pulse distribution to <Xi has been completed based on the main program, and the data indicating that the pulse distribution to the X axis is being executed is erased from the interrotator table RT. Then, pulse distribution to the X axis is started based on the subprogram, and the position of the grinding wheel G is corrected.

When this is completed, the execution of the subprogram is completed and the numerical control device 10 enters the timing state.

Thereafter, each time the start switch is pressed, the above operation is repeated to process the workpiece and correct the grinding wheel, but the grinding wheel G
Since the grinding wheel is corrected in parallel with the backward movement of the grinder, subsequent machining can be started immediately, improving machining efficiency.

As described above, in the present invention, a storage means is provided for storing numerical control programs programmed for each of a plurality of control axes that need to be operated independently of each other, and a storage means is provided for each of the plurality of control axes. A pulse generation circuit is provided which can perform pulse distribution independently of each other in response to pulse distribution command data inputted by the controller, and can independently send out a pulse distribution completion signal, and when a main activation command is given, one control Only pulse distribution processing for the axes is performed according to the corresponding numerical control data, and from the point at which this numerical control data has been executed up to a predetermined step, pulse distribution to other control axes is also performed simultaneously according to other numerical control data. Therefore, it is possible to simultaneously distribute pulses to a plurality of control axes that operate independently from each other from a predetermined point in time, and when such a numerical control device is used in a machine tool such as a grinder, This has the advantage that other operations can be performed during the return operation of the tool, significantly shortening the machining cycle time.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and Figure 1 is a block diagram showing the overall configuration of a numerical control device with a schematic configuration diagram of a grindstone head, and Figures 2 (a) and 2 (b) are a block diagram showing the overall configuration of a numerical control device. Figure 1 shows the numerical control program for machining and the numerical control program for grinding wheel correction stored in the memory 12, Figure 3 shows the detailed circuit of the sequence control circuit 16 in Figure 1, and Figure 4 shows the numerical control program for grinding. Cycle diagram showing an example of a cycle, FIG. 5(a)
, (b) and FIG. 6 are flowcharts showing the operation of the arithmetic processing unit 11 in FIG. It is a chart. 10・φ・Numerical control device, 11... Arithmetic processing device, 1
2...Memory, 13a, 13b...Pulse generation circuit, 15...Program writing device N, 20a, 20b
...speed register, 21a, 21b...oscillator,
22a. 22b @ @ @ preset counter, 23a, 2
3b fist...gate circuit, DT...correction tool, G...
Grinding wheel, W...workpiece. Patent applicant Toyota Machinery Co., Ltd.

Claims (1)

[Claims] (1) In a numerical control device that controls the operation of a machine tool by distributing pulses to multiple control axes, multiple numerical controls each define the movement of multiple control axes that are to be operated independently of each other. A storage means for storing data 7 and a plurality of control axes to be operated independently perform pulse distribution independently according to manual distribution data, and when the distribution is completed, 7J A plurality of pulse generation means that independently send out a distribution completion signal to the controller, and when only the first start command is issued, distribution is performed from the pulse generation means corresponding to a specific axis among the plurality of control axes. Each time a completion signal is sent out, distribution data based on the corresponding numerical control data is set in the pulse generating means to which the distribution completion signal was sent, and both the first start command and the second start command are In the given case, each time the distribution completion signal is sent out between the specific axis and the control axis of a different pond, the distribution completion signal ``f'' is transmitted according to the numerical control data corresponding to the control axis f. a processing means for setting the distributed distribution data to the corresponding pulse distribution means, and generating a second start command in nσ in response to the numerical control program corresponding to the specific control axis being executed to a predetermined position In. A numerical control device characterized in that it is provided with timing control means.