华东交通大学毕业设计
device 42 which is operated under the control of the tool replacement controller 40. When completion of such tool replacement is confirmed in step 82, the tool life (ln-1), tool length revision value (hn-1) and tool diameter revision value (dn-1) for the secondary tool T2110 are read out from the main storage table MIT in step83. These data, along with the tool number of the life-expired primary tool T21, are then transferred as the data relating to the primary tool T21 to the auxiliary controller 20 in a predetermined order in step 84.
Responsive to such tool information, the auxiliary controller 20 executes a routine shown in FIG. 10 to store the transferred data in a receiving buffer not shown in step 90. The transferred tool number is then checked in step 91 to identify a tool to which the transferred tool information relates. If the primary tool T21 is ascertained to relate to the transferred tool information, an area of the tool information table TIT which is allocated to the primary tool T21 is selected in step 92,and the various data included in the received information are in turn written respectively in the corresponding locations of the selected area in step 93, whereby the tool life time (L21), the tool length revision value (H21) and the tool diameter revision value (D21) are revised or modified. In this case, because no tool diameter compensation is to be performed with respect to the primary tool T21, the rewriting of the tool diameter compensation value (D21) does not have any meaning. The usedtime (U21) for the tool T21 is reset by the data rewriting to indicate zero.
In subsequent step 94, the microcomputer 21 instructs the tool change controller 27 to rewrite the information being stored in a storage location table SLT shown in FIG. 11 so that the space tool T01 is regarded as the primary tool T21 and so that the secondary spare tool T2110 which has been set up in the tool magazine TM is regarded as the spare tool T01. Step 95 is next executed, wherein the information on the primary tool 21 is completely replaced with the information on the spare toolT01 in the tool information table TIT. Thus, in the tool exchange operation as well as in the tool dimension compensation processing, the spare tool T01 which has been stored in the tool magazine TM from the beginning is treated as the primary tool T21,and the secondary spare tool T2110 which has been newly stored in the tool magazine TM in place of the primary tool T21 is treated as the spare tool T01. Accordingly, when the spare tool T01 which
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C150普通机床数控化改造
has become the primary tool T21 subsequently reaches the end of its life, the secondary spare tool T2110 is used on the tool spindle TS instead of the spare tool T01, whereby the machining operation of the machine tool MT1 can be continued In the above-described particular embodiment, when a primary tool is replaced with a secondary spare tool therefor, tool information is transmitted along a tool number from the host computer 30 to the auxiliary controller 20 for the purpose of tool information identification. However, the transmission of the tool number is not essential to such tool information identification. For example, it is possible to identify the tool on which the tool information is transmitted from the host computer30, by holding in the auxiliary controller 20 the tool number of the tool for which tool replacement is requested to the host computer 30. Further, in the above-described particular embodiment, the rewriting of dimension revision values is done when a secondary spare tool is set up in a tool magazine in place of a primary tool. However, the present invention is also applicable to the case where the rewriting of dimension revision values is done in conjunction with the replacement of primary tools which accompanies the change in the kind of workpieces to be machined.
Furthermore, it is to be noted that the present invention may be practiced in a machine tool numerical control system wherein no spare tools are parepared in advance in a tool magazine of each machine tool, but wherein any of primary tools, when reaching the end of its life, is replaced with a spare tool therefor which is taken out and transferred from a tool warehouse. Referring now to FIG. 12, there is shown another embodiment of the present invention, wherein the compensation data memory 11 provided in each of the numerical controllers 10 is modified to store one tool dimension compensation value at a time. Each of the tool information table TIT formed in the memory 22 and the main storage table MIT formed in the memory unit 32 are also modified to store, at an storage area for each tool, length and diameter compensation values instead of length and diameter revision values. Further, the NC program is modified to delete therefrom any H-code such as H-21 seen at the N004 program block.
Thus, when the M-code M74 included in the N004 program block of the NC program is
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华东交通大学毕业设计
supplied from the numerical controller 10 to the auxiliary controller 20 as mentioned earlier, not a revision value but a compensation value is read out in step 61or step 62 and is transferred from the auxiliary controller 20 to the numerical controller 10 in step 63. In this case, the transferred compensation value is stored as it is, in the compensation data memory 11 of the numerical controller 10. Further,when executing the routine shown in FIG. 9 in response to the tool replacing command which is generated in step 66 as mentioned previously, the data processor reads out tool information including dimension compensation values, from the main storage table MIT in step 83 and transfers the tool information to the auxiliary controller 20 in step 84. Accordingly, the tool information including the dimension compensation values is processed by the microcomputer 21 in steps 93 and 95.’ It is to be noted that the revision cancel routine shown in FIG. 7 is not executed in the above described second embodiment.
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C150普通机床数控化改造
附录B 外文翻译-译文部分
具有尺寸补偿功能的机床数字控制系统
(1)刀具更换和尺寸补偿操作 图4 图4示例数控程序是利用了刀具长度补偿操作。数控程序准备是为了刀具T21按照N002指令的M06刀具更换要求在机床TM1的刀具TS主轴被收到，快速定位运动按照N003指令的要求实现，为了当N004和N005指令已执行时加工进给运动被执行。刀具T21的刀具长度补偿的编码G43,H21和M74在第一个加工进给指令N004中被执行，取消刀具长度补偿的M75编码在N008指令中被执行直到刀具T21完成的加工。G43编码表明刀具长度补偿被执行的方向是正面或正方向。
现假设机床MT1的数控系统10开始执行数控程序并破译N002指令的要求，T-编码T21输出到与机床MT1相关的辅助控制器20。与辅助控制器20相关的微型计算机21 通过执行主程序确认接收T-编码T21（未显示），执行刀具更换处理程序（如图5）。 图5 因此，第50步首先确认被T-编码T21指定的刀具T21是否过期，与储存在刀具信息TIT中使用寿命（L）的已用时间（U）进行比较。如果还没有到期，微型计算机21将在第51步输出T-编码T21给机床MT1的刀具改变控制器27，然后在第52步发送一个表示与数字控制器10有关的处理已经完成的编码TFIN，由此，指定的刀具T21提出一个显示在TES的刀具更换站（如图1）。
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华东交通大学毕业设计
图1 如果指定的主要刀具T21已经过期，相反，微型计算机21执行第53步，第53步中根据刀具信息表TIT刀具T01被确认为已过期刀具T21为多余刀具。第54步多余刀具T01的刀具编码将被提供给刀具改变控制器27，同样多余刀具T01被交给刀具交换站TES。之后数字控制器10从相同的指令中读出M-编码M06并输出刀具更换命令给刀具改变控制器27，因此主要刀具T21或多余刀具T01被主轴TS接收。数字控制器10在确认刀具更换操作完成后连续执行N003指令和其他指令。
更具体地说，数字控制器10根据N003指令的数控数据执行快速定位运动操作和TS主轴刀具旋转操作，根据指令N004的数值数据执行涉及刀具长度补偿的加工进给控制操作。在进给控制之前，辅助控制器20按照之后描述的补偿储存在补偿数据存储器11中的相应刀具长度值的操作。
数字控制器10读到数控数据“G43 H21 Z-15000 M74”后发送M-编码M74给辅助控制器20，用来请求对H-编码H21指定的补偿值进行修正。当辅助控制器20反馈一个MFIN信号表示完成相应修正，数字控制器10就读出由H-编码H21指定的补偿修正值，并通过将补偿修正值附加给Z轴进给命令“-15000”来修改Z轴进给运动的最终点。时序脉波分布实现了执行Z轴进给运动给补偿终点，由此，加工操作可以用来被编程。
应用辅助控制器20的M-编码M74引起微型计算机21执行补偿值修正程序（如图6）。 根据第55步中多余刀具标记的状态（未显示），在第60步，刀具当前被主轴TS用来作为主要刀具还是多余刀具第一次被检查。第61步和第62步，根据检查结果，主要刀具T21的修正值或者多余刀具T01的其他修正值被读出并输出给数字控制器10。因此，储存在补偿数据存储器11中而且已经根据指令N004被选中的H-编码H21的值，在数字控制器10中被由辅助控制器20提供的修正值修正。
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