Abstract:
A method of operating a machining system includes comparing one or more features of a cutting tool to information stored on a data chip secured to a tool holder of the cutting tool. The cutting tool is loaded into the machining system, and the information stored on the data chip is compared to cutting tool requirements of a machining program for instructing operation of the machine. When a result of one or more of the comparisons is outside of a predetermined threshold, operation of the machining system is stopped.

Description:
FEDERAL RESEARCH STATEMENT 
     This invention was made with Government support under N00019-06-C-0081 awarded by the Department of the Navy. The Government has certain rights in this invention. 
    
    
     BACKGROUND OF THE INVENTION 
     The subject matter disclosed herein relates to industrial machining. More specifically, the present disclosure relates to management and verification of cutting tool data for an industrial machining center. 
     Machining of large complex components requires the removal of a great amount of material from an initial piece of raw material. To achieve this material removal a variety of cutting tools are used, some for long durations of time. Each cutting tool has unique characteristics, such as length, diameter, fluting pattern, etc. One or more cutting program, typically NC programs are developed including cutting tool selection and cutting path for various parts of the machining process. When the program or programs are executed correctly, including using the correct cutting tools and following the correct cutting paths, the result is the desired finished component. If an incorrect cutting tool is used at any point in the process, it may result in collision between the tool or tool holder and the part, or other event which damages or even causes the material to be scrapped. The potential sources of cutting tool error include: 1) the cutting tool does not correspond to the programmer&#39;s intent such that the cutting tool may be set correctly in its tool holder, but may be dimensionally incorrect (length, diameter, shape does not match programmer&#39;s intent; 2) each cutting tool is marked with identifying data in the form of a tag, data chip, or the like on the tool holder, which in some instances, this data may be incorrect; 3) the tool is set in the tool holder incorrectly; or 4) the incorrect cutting tool and tool holder are loaded into the machine for a particular part of the machining program. While the cutting tool is correctly identified, the tool changer apparatus of the machining center may malfunction resulting in the incorrect cutting tool being loaded for use. Reducing or eliminating errors of this sort would result in reduced machining costs through reduction in scrap and/or repair caused by such errors. 
     BRIEF DESCRIPTION OF THE INVENTION 
     According to one aspect of the invention, a method of operating a machining system includes comparing one or more features of a cutting tool to information stored on a data chip secured to a tool holder of the cutting tool. The cutting tool is loaded into the machining system, and the information stored on the data chip is compared to cutting tool requirements of a machining program for instructing operation of the machine. When a result of one or more of the comparisons is outside of a predetermined threshold, operation of the machining system is stopped. 
     According to another aspect of the invention, a machining system includes a machine and a cutting tool operably connectable to the machine. The cutting tool including one or more measurable features. A tool holder is receptive of the cutting tool and includes a data chip including information about the measurable features of the cutting tool. A controller compares contents of the data chip to cutting tool requirements of a machining program for instructing operation of the machine. 
     These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic view of an embodiment of a machining system; 
         FIG. 2  is a view of an embodiment of a cutting tool for a machining system; and 
         FIG. 3  is an illustration of a method of operation of a machining system. 
     
    
    
     The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Shown in  FIG. 1  is a schematic view of a machining system  10 , for example a 5-axis machining system. The machining system  10  includes a machine  12  having a cutting tool  14  at an end of the machine  12 . The cutting tool  14  is held in a tool holder  16 . When the machining system  10  is operating, the cutting tool  14  rotates about a tool axis and removes material from a workpiece  18  shown on a worktable  20 . In some embodiments, the worktable  20  is moveable, translating and/or rotating as desired. Machining of the workpiece  18  is controlled by a controller  22  operably connected to the machine  10 . One or more machining programs are loaded into the controller  22  providing instructions regarding path of the cutting tool  14  and also identifying information regarding which cutting tool  14  is used for each portion of the machining program. The various cutting tool  14 /tool holder  16  assemblies are located in a tool magazine  24  for retrieval by the machine  12  when instructed by the program. Referring to  FIG. 2 , the tool holder  16  includes a data chip  26  in which identifying data is stored regarding the cutting tool  14  in the tool holder  16 . When the tool holder  16 /cutting tool  14  assemblies are loaded into the tool magazine  24 , the tool magazine  24  reads the data chip  26  and transmits the cutting tool  14  location in the tool magazine  24  to the controller  22 . 
     Referring to  FIG. 3 , a method will now be described to verify that the correct cutting tool  14  is utilized when called for by the machining program. As stated above, each tool holder  16 /cutting tool  14  assembly is identified with information regarding the cutting tool  14  installed in the tool holder  16 . This information is stored on a data chip  26  secured to the tool holder  16 . This information includes, for example, tool length, tool diameter, tool type, or the like. Prior to the cutting tool  14 /tool holder  16  being loaded into the tool magazine  24 , a cutting tool diameter  28 , cutting tool length  30 , and/or other pertinent features are measured in block  100 , either by an operator, or by a machine probe (not shown). The measured features are compared with the information stored on the data chip  26  in block  102  to verify that the data chip  26  contains accurate information regarding the particular cutting tool  14 . This process is repeated for each cutting tool  14  loaded into the tool magazine  24 . In block  104 , if measured data matches the data chip  26  within a threshold, the cutting tool  14  is loaded in the tool magazine  24  for use in block  106 . If the data is outside of the threshold, in block  108  the cutting tool  14  is not loaded into the tool magazine  24  before the information on the data chip  26  is modified to correspond to the actual cutting tool  14  measurements. 
     Next, when a cutting tool  14  is installed in the machine  10  for use in block  112 , either at the beginning or at a tool change step of the machining program, a subprogram in the controller  22  is initiated. This subprogram compares, in some embodiments the comparison occurs automatically, the information on the data chip  26  with the cutting tool diameter  28  and cutting tool length  30  and other cutting tool  14  information called for by the program in block  114 . This “soft check” block  110  verifies that the information on the data chip  26  matches the intent of the programmer. In block  116 , if the comparison results in a value outside of a threshold, for example, a cutting tool diameter  28  is too small or too large, or a cutting tool length  30  is too short or too long, an alarm is initiated and the machine  10  will not operate with such a cutting tool  14  installed as in block  118 . 
     Once the soft check is completed, a hard check, block  120 , is performed to verify that the actual cutting tool  14 , not just the data chip  26 , matches the intent of the programmer In this hard check, once the cutting tool  14  is loaded into the machine  10 , then in block  122  one or more features such as cutting tool diameter  28  and/or cutting tool length  30  are measured, either manually by the operator or by use of the machine touch probe. In block  124 , the measurement(s) are compared to the cutting tool  14  information called for by the program. This verifies that: 1) the cutting tool  14  information corresponds with the information residing on the data chip  26  and 2) that the actual cutting tool  14  features match the cutting tool  14  required by the program. This is useful not only in situations where the incorrect tool is loaded into a tool holder  16  or the incorrect data is on the data chip  26 , but in cases where a cutting tool  14  is used over a long period of time in a particular program and has become worn, so that when reloaded into the machine  10  the cutting tool  14  no longer meets the intent of the programmer As with the soft check, if the measurements of the cutting tool  14  fall outside of a selected threshold in block  126 , the alarm is initiated in block  128  and the machine  10  will not operate with such a cutting tool  14  installed. If the result of the comparison is within the threshold, the machine  10  will operate in block  130  with the cutting tool  14  installed. 
     While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.