JPH0310768A - Numerically controlled grinding machine - Google Patents

Abstract

PURPOSE:To perform multidress according to a simple processing program by providing a control means which the machining allowance of a work specified at one full grinding cycle is divided by an allowable machining allowance and executes one full dress cycle and one full grinding cycle with each division machining allowance. CONSTITUTION:One full dress cycle, a grinding cycle, and a machining allowance capable of being ground at one full dress are stored in each of memory parts 6, 9, and 10. The machining allowance of a work specified at one full grinding cycle is divided by an allowable machining allowance stored in a control means 8, and the stored one full dress cycle and one full grinding cycle stored at each division machining allowance are executed.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a numerical control (NC) grinding machine that grinds a workpiece by alternately executing a dressing cycle for dressing and a grinding cycle for grinding. Regarding.

(Prior Art) When grinding a workpiece, chips from the workpiece and abrasive grains that fall off the whetstone cause the whetstone to become clogged or crushed, reducing the sharpness of the whetstone.

Therefore, the whetstone is dressed to remove chips and abrasive grains and restore its sharpness.

When grinding the machined surface of a workpiece with a large machining allowance, divide the machining allowance into machining allowances that are less than the allowable machining allowance that can be ground with one dressing of the grindstone, and dress the divided machining allowance each time the grinding process is performed. It is necessary to maintain the sharpness of the whetstone. A grinding process in which grinding and dressing are performed multiple times in order to grind one machined surface in this manner is called multi-dressing.

FIG. 4 is a plan view of an example of the grinding section of an NC grinding machine capable of performing the multi-dressing described above.
A grindstone head 21 movable in the X-axis direction and a table 24 facing the moving direction of the whetstone head 21 and movable in the Z-axis direction are placed on top. A disk-shaped grindstone 22 is attached to the grindstone head 21, and a headstock 26 and a tailstock 27 that hold a workpiece 25 are placed on the table 24. Furthermore, a diamond 23 is provided on the headstock 26.
is attached facing the grindstone 22.

In such a configuration, an example of its operation will be explained with reference to FIG. 5. As the grindstone head 21 and table 24 move, the diamond 23 dresses the grindstone 22 (arrow ■ in the figure). After that, by moving the whetstone head 21 and table 24, the whetstone 2
2 is located at the starting point of the grinding process, indicated by the arrow ■), and the grindstone head 2
1, the grindstone 22 grinds the workpiece 25 by a predetermined machining allowance (arrow ■ in the figure). Thereafter, the grindstone 22 returns to the dressing starting point by the movement of the grindstone head 21 and table 24 (arrow ■ in the figure), and thereafter the operations from ■ to ■ described above are repeated.

In the grinding process, as shown in FIG. 6, it may be necessary to consider the deflection BQ of the workpiece (especially a long workpiece) 25. For example, when grinding is performed by dividing the machining allowance TQ of the machined surface of the workpiece 25 into the allowable machining allowance VQ of the grindstone 22 as shown in FIG. -+ is located on the grindstone 22 side by 80 minutes of deflection from the i-1th grinding cycle end point PEl-2. Therefore, if the X-coordinate position and Z-coordinate position of the grinding cycle start point and the grinding cycle end point are ps□, ps, and PEox, PEn, respectively, there is a relationship expressed by the following equation (1).

PS,,=PEf,,-1)x+BQ
---(1) However, n-1, 2, 3,...
...Note that WP is a grindstone command point relative to the program origin 0 with the workpiece 25 as a reference.

FIG. 8 is an example of a Canadian program that performs multi-dressing in consideration of the above-mentioned deflection.

First of all, the first dress cycle is illustrated (■), 1
Positioning to the starting point PS of the second grinding cycle is executed (■ in the figure), and a grinding cycle is executed to carry out grinding for the allowable machining allowance yQ (■ in the figure).

Next, the second 1-res cycle is illustrated (■),
Position PS closer to the grinding wheel by deflection BQ from the end point of the first grinding cycle PEG, (starting point of the second grinding cycle)
Execute the positioning (as shown in the diagram), and execute the grinding cycle that performs the grinding process for the allowable machining allowance VQ + 80 minutes (
Illustration @). This operation is repeated until the machining allowance TQ of the workpiece is reached. However, the machining allowance TQ and the allowable machining allowance VO usually have a relationship expressed by the following equation (2).

TQ=VQ-■+IIQ (to-1, 2, 3・
...) ...(2) In formula (2), RQ indicates the machining allowance of a half portion, and has the value of VQ not yet grooved. Therefore, in this example, the machining allowance for the final 4Ji cutting cycle (0 in the figure) is RQ+BQ.

(Problems to be Solved by the Invention) When performing multi-dressing with the above-mentioned NC grinding machine, the greater the machining allowance of the workpiece is than the allowable machining allowance of the grinding wheel, the more the number of repetitions of the dressing cycle and the grinding cycle increases. The disadvantage was that the Canadian program became redundant. Also, if you want to change the allowable machining allowance, you must change all the allowable machining allowances commanded in the Canadian program, and then recalculate the number of dress cycles and grinding cycles and delete the dress cycle and grinding cycle. Otherwise, the problem is that it takes too much time and it is easy to make programming mistakes.

The present invention was made in view of the above-mentioned circumstances, and an object of the present invention is to provide an NC grinding machine that can perform multi-dressing with a simple cannibal program and can easily change the cannibal program. Our goal is to provide the following.

(Means for Solving the Problems) The present invention relates to an NC grinding machine that grinds a workpiece by alternately executing a dressing cycle for dressing and a grinding cycle for grinding. The purpose is to provide a means for storing one dressing cycle, a means for storing one grinding cycle, a means for storing an allowable machining allowance that can be ground by one dressing, and one dressing cycle. means for storing a position before the start of execution of the grinding cycle, and means for dividing the machining allowance of the workpiece designated for the one grinding cycle by the allowable machining allowance, and for each divided machining allowance, the one dressing cycle and the one grinding cycle. and control means for executing the grinding cycle.

(Function) The NC grinding machine of the present invention stores one dress cycle and one grinding cycle, and returns to the position for performing the next grinding cycle after finishing the dress cycle. Therefore, multi-dressing can be performed by simply instructing one dressing cycle, one grinding cycle, and the allowable machining allowance.

(Embodiment) FIG. 1 is a block diagram showing an example of the control section of the NC grinding machine of the present invention. The Canadian Niprogram SR that is currently being read out is read out by the Cannibal Program control section 3 and edited, and the edited Canadian Niprogram program SC is sent to the Cannibal Program analysis section 5 and analyzed. The analyzed carnivorous program SO is sent to the grinding control unit 8, and the grinding cycle SE, dress cycle SF, and allowable machining allowance (including the deflection if the workpiece deflection is specified) specified in the machine program 50 are sent to the grinding control unit 8. SG and the position SH before the start of execution of the dress cycle are stored in the grinding cycle storage unit 6. Dress cycle storage section 9. Allowable machining allowance storage part I
The X-axis motor 13 and the Z-glaze motor 14 are respectively stored in the O and return position storage sections II, and are controlled via the axis drive device 12.

In such a configuration, an example of the operation of the grinding control unit 8, which is the main part, will be explained with reference to the flowchart in FIG. Read the block (step S1), check whether it is multi-dress mode or not using the flag MD (step S21゜If MO・0, check whether a multi-dress mode person is specified in the read block. (Step S3) If the multi-dress mode person is specified, the allowable machining allowance (or the number of divisions) specified for the same block is stored, and if the workpiece deflection is specified, the deflection is also stored. 10 (Step S4).Furthermore, the dress cycle of the sequence salt specified in the same block is searched and stored in the dress cycle storage section 9 (Step S5). MO is set to "1" (step S6). Then, it is checked whether a dress cycle to be executed during multi-dress is specified for the same block (step 510),
If a dress cycle is specified, empty reading of the block is performed until the end of the dress cycle so as not to execute the dress cycle (step 511), and step 521
Proceed to. On the other hand, if the multi-dress mode person is not specified in the judgment step S3, or if the dress cycle is not specified in the judgment step 510, normal operation is performed (step 512), and the process proceeds to step 521.

On the other hand, in the judgment step S2, in the case of MO-1, it is checked whether or not multi-dress mode off is specified for the read block.In step S7), if multi-dress mode off is specified, “0” for NO
゛° is set in step S8), and the process proceeds to step 521. Further, if multi-dress mode cutting is not specified, it is checked whether a grinding cycle is specified for the same block (step S9), and if a grinding cycle is not specified, the process proceeds to step 510. The above-mentioned operation is performed, and when the grinding cycle is set to +b, the multi-dress described below is executed.

First, the grinding cycle of the same block is stored in the grinding cycle storage unit 6, the machining allowance of the work specified in the same block is set to internal variable A, and the internal variable B for machining allowance accumulation is set to "0" (step 513 ). Next, the current position of the x and Z axes is stored in the return position storage unit 10 (step 514).
, the dress cycle stored in step S5 is read out and executed (step 515), and positioning is performed to the return position stored in step 514 (step 515).
). Then, the machining allowance for one grinding cycle is calculated and set in internal variable C (step 517). The machining allowance calculated here is equal to the allowable machining allowance if the allowable machining allowance was specified in step S4, and if the number of molecules II is specified, the machining allowance of the workpiece specified in step 513 is divided into the number It is equal to the value divided by , and if the deflection of the workpiece is specified, the deflection is also added. Next, grinding cycle 1 set in internal variable C
Step 518) Execute one grinding cycle for each machining allowance, grinding cycle 1 set in internal variable C.
Add the machining allowance for each batch to the value of internal variable B for machining allowance accumulation (step 519), and step 51 until the value of internal variable B for machining allowance accumulation becomes greater than or equal to the machining allowance of the workpiece set in internal variable A.
4 to S19 are repeated (step 520). If the value of the internal variable B for machining allowance accumulation exceeds the machining allowance of the workpiece set in the internal variable A, the next block of the cutting program is read (step 521), and steps 52 to 522 are carried out until the end of the program. The operation of step 522) is repeated, and when the program end is read, all processing is completed.

Figure 3 is an example of a machine program for performing multi-dressing in consideration of deflection in the NC grinding machine of the present invention.
181'' “0180” specifies the start and end of the Canadian program that specifies the dress cycle. “G
DIN NCH3QG-VQ QE-BQ" is a block that specifies the multi-dress mode user, the sequence name NDIIS of the dress cycle start block, the allowable machining distance VQ of the grinding wheel, and the deflection 8Q of the workpiece. "GDOIIT" specifies the multi-dress mode off. This is an example of a cutting program (No. 8) for a conventional NC grinding machine.
Compared to the example shown in FIG. 3, the example of the cutting program for the NC grinding machine of the present invention (FIG. 3) is simpler and easier to change.

(Effects of the Invention) As described above, according to the NC grinding machine of the present invention, it is possible to easily create and change a carnivorous program that commands multi-dressing, thereby significantly shortening the creation time of the carnivorous program, and It is possible to reduce production errors and start reliable grinding quickly.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of the control unit of the NC grinder of the present invention, FIG. 2 is a flowchart explaining an example of its operation, and FIG. 3 is a diagram showing an example of a cutting program used in the NC grinder of the present invention. , Fig. 4 is a plan view showing an example of the grinding part of a general NC grinder, Figs. 5 to 7 are diagrams for explaining the grinding process, and Fig. 8 is used in a conventional NC grinder. FIG. 2 is a diagram showing an example of a Canadian program. DESCRIPTION OF SYMBOLS 1... Operation panel, 2... Display device, 3... Cannibal program control section, 4... Cannibal program buffer, 5...
. . . Machine program analysis section, 6. Grinding cycle storage section, 8. Grinding control section, 9. Dress cycle storage section, IO.. Allowable machining allowance storage section, 11. Part, 12... Axis gA movement device, 13... X-axis motor, 14... Z-axis motor, 20... Bed, 21
...Whetstone stand, 22...Whetstone, 23...Diamond, 24...Table, 25...Workpiece, 26...
・Main/spindle stock, 27...Tailstock. NDR8 0181 (3DIN NDR3Q (3 = VQ QE = BQ Yu3

Claims (1)

[Scope of Claims] 1. In a numerically controlled grinding machine that grinds a workpiece by alternately executing a dressing cycle for dressing and a grinding cycle for grinding, means for storing one dressing cycle; means for storing one grinding cycle; means for storing an allowable machining allowance that can be ground by one dressing; and dividing the machining allowance of the workpiece designated for one grinding cycle by the allowable machining allowance. A numerically controlled grinding machine characterized by comprising: a control means for executing the one dressing cycle and the one grinding cycle for each divided machining allowance. 2. The numerically controlled grinding machine according to claim 1, further comprising means for storing the number of divisions of the machining allowance of the workpiece instead of the means for storing the allowable machining allowance. 3. Means for storing a position before the start of execution of the one dress cycle is provided, and the control means returns to the position before the start of execution of the one dress cycle after the execution of the one dress cycle is finished. The numerically controlled grinding machine according to claim 1 or 2, wherein the numerically controlled grinding machine is configured to perform positioning. 4. The means for storing the allowable machining allowance stores the deflection of the workpiece that occurs during the grinding, and the control means executes the one grinding cycle by adding the deflection of the workpiece to the divided machining allowance. 2. The numerically controlled grinding machine according to claim 1, wherein return positioning is performed to a position returned by an amount corresponding to the deflection of the workpiece from a position before the start of execution of the one dress cycle.