C150普通机床数控化改造
参考文献
【1】刘小年，等.机械设计制图简明手册.北京：机械工业出版社，2000. 【2】罗永顺. 机床数控化改造实例.北京：机械工业出版社，2009.
【3】范云涨，陈兆年. 金属切削机床简明手册.北京：机械工业出版社，1994. 【4】廖效果.数字控制机床.武汉：华中科技大学出版社，1992. 【5】濮良贵，等．机械设计．北京：高等教育出版社，2003. 【6】罗永顺.机床数控化改造技术.北京：机械工业出版社，2007.
【7】上海纺织工学院，等.机床设计图册.上海.上海科学技术出版社，1979. 【8】明兴祖.数控机床与系统.北京:中国人民大学出版社，2000.
【9】机械工业出版社编.机床设计手册.北京：机械工业出版社，1992. 【10】孙桓，陈作模.机械原理.北京：高等教育出版社，2001. 【11】洪家娣，等.机械设计指导.南昌：江西高校出版社，2006．
【12】机床设计手册编写组.机床设计手册：第三册.北京：机械工业出版社，1986. 【13】机床设计手册编写组.机床设计手册：第二册.北京：机械工业出版社，1980. 【14】廖效果.数控技术.武汉：湖北科学技术出版社，2005.
【15】刘庶民.机床改造的思路与实用技术.北京：机械工业出版社，1993. 【16】L.Meivovitch.“Elements of Vibration analysis”. MCGRAW—HILL,1995
【17】Yoram Koren. Computer Control of Manufacturing System. McGram Hill Book Co. 1983
附录A 外文翻译-原文部分
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华东交通大学毕业设计
Numerical control system for a machine tool with a
tool dimension compensation function
（1）Tool Exchange and Dimension Compensation Operations
FIG. 4 exemplifies an NC program utilizing a tool length compensation operation. The NC program is so prepared that a tool T21 is received in a tool spindle TS of the machine tool TM1 in accordance with a tool exchange command M06 of the N002 program block, that rapid positioning movements are effected in accordance with commands of the N003 program block, and that machining feed movements are performed when the N004 and N005 program blocks are executed. Codes G43, H21 and M74 for instructing a tool length compensation on the tool T21 is programmed in the first machining feed program block N004, whereas a code M75 for cancelling the tool length compensation is programed in the N008 program block successive to the completion of a machining by the tool T21. The code G43 represents that the direction in which the tool length compensation is to be done is a positive or plus direction. Assuming now that the numerical controller 10 for the machine tool MT1 begins to execute the NC program and decodes the commands of the N002 program block, the T-code T21 is output to the auxiliary controller 20 associated with the machine tool MT1. The microcomputer 21 of the associated auxiliary controller 20 recognizes the receipt of the T-code T21 by executing a main routine not shown and executes a tool exchange processing routine shown in FIG. 5. Thus, it is first ascertained in step 50 whether the life of the primary tool T21 designated by the T-code T21 has expired or not, in comparison of the used time (U) with the life time (L) which are stored in the tool information TIT. If it has not expired yet, the microcomputer 21 outputs theT-code T21 to the tool change controller 27 of the machine tool MT1 in step 51 and then, sends a code TFIN representing the completion of this processing to the associated numerical controller 10 in step 52, whereby the designated primary tool T21 is presented to a tool exchange station indicated at TES in FIG. 1.
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C150普通机床数控化改造
If the life of the designated primary tool T21 has already expired, to the contrary, the microcomputer 21 executes step 53, wherein a tool T01 is ascertained to be a spare tool for the life-expired tool T21 by reference to the tool information table TIT. The tool number of this spare tool T01 is supplied to the tool change controller 27 in step 54, whereby the spare tool T01 is presented to the tool exchange station TES. The numerical controller 10 then reads out an M-code M06 from the same program block to output a tool exchange command to the tool change controller 27, so that the primary tool T21 or the spare tool T01 therefor is received in the tool spindle TS. The numerical controller 10 further executes the N003 program block and other blocks successive thereto after confirming the completion of the tool exchange operation.
More specifically, the numerical controller 10 executes the processing for rapid positioning movements and the processing for rotation of the tool spindle TS in accordance with NC data of the N003 program block and then, executes a machining feed control involving a tool length compensation, in accordance with NC data of the N004 program block. Prior to this feed control, the auxiliary controller 20 executes the processing for revising the corresponding tool length compensation value being stored in the compensation data memory 11, in the manner as described hereunder in detail.
Reading NC data \M74 to the auxiliary controller 20 to request the revision of the compensation value designated by an H-code H21. When the auxiliary controller 20 feeds back a signal MFIN upon completion of such revision, the numerical controller 10 reads out the revised compensation value designated by the H-code H21, and modifies the end point of Z-axis feed movement by adding the revised compensation value to the read-out Z-axis feed command \Pulse distribution is effected to perform the Z-axis feed movement toward the compensated end point, whereby a machining operation is performed as programmed.
The application of the M-code M74 to the auxiliary controller 20 causes the microcomputer 21 to execute a compensation value revising routine shown in FIG. 6. Whether the tool currently in use on the tool spindle TS is a primary tool or a sparetool therefor is first checked in step 60 by reference to the state of a spare tool flag not shown which was set in step
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华东交通大学毕业设计
55. A revision value for the primary tool T21 or another revision value for the spare tool T01 is read out in step 61 or step 62depending upon the result of such checking and is output to the numerical controller 10. Consequently, the value of the H-code H21 which is stored in the compensation data memory 11 and which has been selected in accordance with the N004 program block is revised by the revision value supplied from the auxiliary controller 20, in the numerical controller 10. It is to be noted here in that the compensation of tool length is unnecessary where any primary tool such as the tool T21 is used on the tool spindle TS. To this end, an address of the compensation data memory 11 for the H-code H21 has been be forehand set with a dimension compensation value indicating zero (0), and the revision value H21 being stored in the tool information table TIT in correspondence with the primary tool T21 has been initially chosen to indicate zero. In this connection,the revision value H01 which has been stored in advance in the tool information table TIT for the spare tool T01 indicates the difference in dimension between the primary tool T21 and the spare tool T01. It is also to be noted that because of a limited bit number at the revision value input terminal 12, each compensation value in the numerical controller 10 cannot be revised more than 7.999 millimeters at a time. Therefore, when revising a compensation value more than 7.999 millimeters, the microcomputer 21 under the control of a revision value transfer routine shown in FIG. 8 sends the whole of a revision value to the numerical controller 10 in such a manner that a maximum unit revision value Vmax which may be an integer smaller than 7.999 is sent one or more times in steps 63c before the successive sending of the fraction in step 63g.
The numerical controller 10 modifies the Z-axis feed command \compensation value H21 which has been subjected to revision in the foregoing manner and distributes feel pulses in accordance with the modified Z-axis feedcommand. Accordingly, it is possible to perform a desired machining even when a spare tool is subsequently used instead of the primary tool.
Further, when the M-code M74 is supplied to the auxiliary controller 20, the microcomputer 21 in step 65 ascertains whether the replacement of the life-expired primary tool
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C150普通机床数控化改造
T21 with the spare tool T01 has been completed or not, by checking the state of a flag not shown which has been reset since the life of the primary tool T21 was ascertatined to have expired in step 50. If the flag has still been reset, in other words, if such replacement has not been completed yet, the microcomputer 21transfers a tool replacing command along with the tool number of the life-expired tool T21 to the host computer 30 in step 66.
On the other hand, when M-code data M75 in the N008 program block is read out by the numerical controller 10 to be output to the auxiliary controller 20, the same executes a revision cancel routine shown in FIG. 7 for cancelling the revision from the outside. That is, the microcomputer 21 in step 70 sets cancelling data which is the same value as the revision value that it supplied to the numerical controller 10 in response to the M-code M74, but which has the opposite sign and then, supplies the cancelling data to the numerical controller 10 in the same manner as described above. As a result, the compensation value designated by the H-code H21 is returned to the previous or initial value. （2） Tool Replacing Operation
When the spare tool T01 is put in use as a result of the expiration of the life of the above-noted primary tool T21, the tool replacing command is supplied along with the tool number of the primary tool T21 from the auxiliary controller 20 to the host computer 30, as mentioned earlier in connection with step 66. Thus, the host computer 30 executes a routine shown in FIG. 9 in response thereto.
Step 80 is first executed, wherein based upon the life-expired tool number T21 transferred from the auxiliary controller 20, the spare tool table SIT is searched for a secondary spare tool T2110 which is stored in the tool warehouse (not shown)for replacement of the life-expired primary tool T21. The control number of the searched secondary spare tool T2110 is then sent to the tool replacement controller 40 in step 81. Consequently, the secondary spare tool T2110 is taken out from the tool warehouse, is transferred to the vicinity of the tool magazine TM storing the life-expired primary tool T21 and is replaced with the same to be set up in the tool magazine TM. Such tool taking-out, transfer and replacement operations are done by thetool replacing
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