GB2110425A - Machining control method for milling - Google Patents

Machining control method for milling Download PDF

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Publication number
GB2110425A
GB2110425A GB08232632A GB8232632A GB2110425A GB 2110425 A GB2110425 A GB 2110425A GB 08232632 A GB08232632 A GB 08232632A GB 8232632 A GB8232632 A GB 8232632A GB 2110425 A GB2110425 A GB 2110425A
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GB
United Kingdom
Prior art keywords
machining
unit
machining unit
tool
milling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08232632A
Other versions
GB2110425B (en
Inventor
Hiroyuki Kanematsu
Susumu Nishiwaki
Hajime Ohashi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yamazaki Mazak Corp
Original Assignee
Yamazaki Machinery Works Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Yamazaki Machinery Works Ltd filed Critical Yamazaki Machinery Works Ltd
Publication of GB2110425A publication Critical patent/GB2110425A/en
Application granted granted Critical
Publication of GB2110425B publication Critical patent/GB2110425B/en
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
    • G05B19/4093—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by part programming, e.g. entry of geometrical information as taken from a technical drawing, combining this with machining and material information to obtain control information, named part programme, for the NC machine
    • G05B19/40937—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by part programming, e.g. entry of geometrical information as taken from a technical drawing, combining this with machining and material information to obtain control information, named part programme, for the NC machine concerning programming of machining or material parameters, pocket machining
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23C—MILLING
    • B23C3/00—Milling particular work; Special milling operations; Machines therefor
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/30—Nc systems
    • G05B2219/36—Nc in input of data, input key till input tape
    • G05B2219/36333—Selection from standard forms, shapes, partprograms, enter value for variable
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/30—Nc systems
    • G05B2219/49—Nc machine tool, till multiple
    • G05B2219/49282—Same control for double drive or slide
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/30—Nc systems
    • G05B2219/49—Nc machine tool, till multiple
    • G05B2219/49381—Raster, line servo, area machining, cutting, facing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
    • Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Human Computer Interaction (AREA)
  • Manufacturing & Machinery (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Mechanical Engineering (AREA)
  • Numerical Control (AREA)
  • Milling Processes (AREA)

Abstract

The method comprises sorting the milling into a plurality of machining units, each representing an elementary end or face milling operation, in accordance with the machining shape, storing machining patterns corresponding to the machining units in a machining pattern memory reading, when one of said machining units is inputted, the machining pattern corresponding to the inputted machining unit by a search through the machining pattern memory, and computing and determining the final tool path in accordance with the read out machining pattern.

Description

SPECIFICATION Machining control method for milling The present invention relates to a machining control method for controlled milling performed by a numerical control machine tool.
Hitherto, in carrying out a milling by means of a machine tool of the kind described, it has been necessary to determine tool paths necessary for obtaining the required machining shape and to form and input a program to the machine tool by a skilled programmer having a good knowledge in the field concerned.
In recent years, a machining method has been proposed in which the desired machining shape is sorted and broken down into a plurality of machining units to permit the operator, without any assist by the programmer, to directly input the selected machining units to the machine tool which in turn forms and executes a machining program in accordance with the inputted machining units. In this method, however, the operator is burdened excessively in the determination of the tool paths at each time of the machining. Under this circumstance, there is an increasing demand for development of a machining control method which can unburden the operator.
Accordingly, it is an object of the invention to provide a machining control method for milling performed by a numerical control machine tool, improved to eliminate the necessity for determination of tool paths by a programmer or an operator.
To this end, according to the invention, there is provided a machining control method for milling performed by a numerical control machine tool comprising: sorting the milling into a plurality of machining units in accordance with the machining shape, storing machining patterns corresponding to the machining units within a machining pattern memory, reading; when one of said machining units is inputted, the machining pattern corresponding to the inputted machining unit out of the machining pattern memory, and computing and determining the final tool path in accordance with the read out machining pattern.
Preferred features of the invention are set forth in claims 2 to 4.
The invention will now be more particularly described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a control block diagram showing a numerical control machine tool to which the invention is applied; Figure 2 is a chart showing the sorting and classification of machining into machining modes and machining units; Figure 3 is an illustration of machining patterns corresponding to the machining units; and Figures 4a and 4b are illustrations of an example of actual machining.
Referring first to Figure 1, a numerical control machine tool generally designated at a numeral 1 has a main control unit 2 to which are connected a tool path computing control unit 3, tool file 5, program memory 6, input control unit 7, display unit 9 and a keyboard 10. The tool file 5 stores various data concerning the tools to be used such as names, diameters, lengths, number of blades and so forth. A machining pattern memory 11 is connected to the tool path computing control unit 3. A machining mode developing memory 12, machining unit developing memory 13 and a machining shape developing memory 1 5 are connected to the input control unit 7.
In the operation of the numerical control machine tool having the described construction, the main control unit 2 reads the machining mode MODE from the machining developing memory 12 through the input control unit 7, and the read out machining mode MODE is displayed on the display unit 9.
More specifically, the milling is sorted in accordance with the machining shape into a line machining mode making use of an end mill or the like tool and a surface machining mode which is to be achieved by a face mill or the like tool, as shown in Figure 2. Consuiting with the machining drawings, the operator judges to which one of these two modes the machining to be conducted belongs, and inputs the selected machining mode MODE through the keyboard 10. Upon receipt of the machining mode MODE, the input control unit 7 reads machining units belonging to the inputted machining mode MODE out of the content of the machining unit developing memory 13. The read out machining units are put on the display.The machining unit developing memory 13 stores the names of the machining units belonging to each machining mode MODE in a manner corresponding to each machining shape as shown in Figure 2. Each machining unit is adapted for performing an elementary machining operation as illustrated in Figure 3.
Then, the operator selects the names of the machining units to be performed from the names displayed on the display unit 9 with reference to the machining drawings, and inputs the selected machining units through the keyboard 10. Then, the input control unit 7 reads out of the content of the machining shape developing memory 15 the machining condition factors KJ such as tool stroke, cutting depth or penetration, amount to be removed by chamferring, class of finishing and so forth. These factors KJ are put on display on the display 9 to permit the operator to select and input the necessary machining data DATA. The machining shape developing memory 1 5 stores machining condition factors KJ for determining the nature of each machining unit.The arrangement is such that, once any machining unit is appointed, the machining condition factors KJ necessary for the appointed machining unit are read out without delay. Then, the operator successively inputs, as the machining data DATA, actual numerical values or other conditions for each of the factors KJ on the display unit 9, upon consultation with the machining drawings.
On the other hand, the tool path computing control unit 3 makes a search through the machining pattern memory 11 by the name of the machining units to determine the paths along which the tool is to be moved in the execution of this machining unit. Namely, as will be seen from Figure 3, the pattern memory 11 stores machining patterns PAT corresponding to respective machining units. For instance, a line center machining unit (Al) is a machining pattern PAT in which the tool is moved with its center CR following a path PASS interconnecting a starting point SPT and a finishing point FPT which are inputted by the operator.Similarly, a line right machining unit (A2) and a line left machining unit (A3) are machining patterns PAT in which the tool is moved along the path PASS inputted by the operator with the tool center CR offset to the right and left, respectively, by a predetermined amount from the path PASS.
A line outer machining unit (A4) has a machining pattern PAT in which the path is determined in accordance with the shape SHP of the work inputted by the operator so that the tool 1 6 is moved along the outer surface of the work to machine the latter.
In contrast, a line inner machining unit (A5) is a machining pattern in which the path is determined in accordance with the shape SHP of the work inputted by the operator as in the case of the line outer machining unit (A4) but the tool is moved along the inner peripheral surface of the work.
A chamfer right machining unit (A6) is a machining pattern in which the portion of the work at the right side of a path PASS inputted by the operator is chamfered while the portion at the left side of the path PASS is left unchamfered. In achieving this machining pattern, the tool 1 6 is moved at a predetermined rightward offset from the path PASS.
In contrast, a chamfer left machining unit (A7) is a machining pattern in which the portion of the work at the left side of the path PASS is chamfered while the portion at the right side is left unchamfered. To this end, the tool is moved at a predetermined leftward offset from the path PASS.
A chamfer outer machining unit (A8) is a machining pattern PAT in which the path PASS is determined in accordance with the shape SHP of the work inputted by the operator to make the tool 1 6 move along the outer surface of the work to effect a chamfering.
In contrast, a chamfer inner machining unit (A9) is a machining pattern PAT in which the path PASS is determined in accordance with the shape SHP of the work inputted by the operator as in the case of the chamfer outer machining unit (A8) but the tool 1 6 is moved along the inner surface of the work to effect a chamfering.
A face mill machining unit (B10), end mill surface machining unit (B1 1) and a pocket end mill machining unit (B1 3) are machining patterns in which the tool 1 6 is moved following up respective illustrated cutting patterns CPT in accordance with the shape SHP of the work (coordinates) inputted by the operator, thereby to cut the hatched areas.
An end mill crest machining unit (B1 2), pocket end mill crest machining unit (B14) and the pocket end mill valley machining unit (B1 5) are machining patterns PAT in which the tool 1 6 is moved following predetermined cutting patterns CPT in accordance with the shape SHP of the work inputted by the operator thereby to effect the cutting of the two hatched areas in respective sketches.
An end mill groove machining unit (B1 6) is a machining pattern in which the tool 1 6 is moved following up a predetermined cutting pattern CPT in accordance with the shape SHP of the work inputted by the operator to effect a cutting of the area enclosed by an ellipse in the sketch.
The machining condition factors KJ which are inputted by the operator together with the machining units include the tool stroke H1, cutting depth or penetration t1, t2, chamfering amount C, shown in Figure 3 and so forth. Upon receipt of this machining data DATA, the main control unit 2 selects the optimum tool for use in the machining, out of the tool file memory 6. The main control unit 2 then informs the tool path computing control unit 3 of the selected tool. The control unit 3 then computes and determines the final tool paths for the tools 1 6 from the machining data DATA and the diameters and lengths of the selected tools 16, in such a manner as to correct the machining pattern PAT read out from the machining pattern memory 11, and the thus computed tool path is stored as a machining program PRO in the program memory 6.
The actual machining is conducted in accordance with the machining program PRO stored in the program memory 6. For instance, to form by cutting a pocket 1 7b having a central protrusion 1 7a from a tabular work 1 7 as shown in Figure 4a, the operator appoints through the keyboard 10 the pocket end mill crest machining unit B14 and, at the same time, inputs the shapes of the pocket 1 7b and the protrusion 1 7a in the form of coordinate values, as well as the tool stroke H, and the cutting depth t,. In response to these inputs, the main control unit 2 selects out of the tools filed in the tool file 5 an end mill having a blade number, diameter and length most appropriate for the present machining, and informs the computing control unit 3 of the nature of this end mill. Upon receipt of this information concerning the end mill, the computing control unit 3 computes the final tool path K taking into account both of the cutting pattern CPT constituting the machining pattern PAT read out from the machining pattern memory 11 and the shapes of the pocket 1 7b and the protrusion 1 7a inputted by the operator, as well as other necessary factors. Namely, the machining by the tool 1 6 is started from the point P 1 shown in Fig.
4a and is then moved in accordance with the cutting pattern CPT. Namely, the tool 1 6 is first moved to machine the area between the wall of the pocket 1 7b and the protrusion 1 7a. To this end, the tool 1 6 is moved along paths K similar to the profile of the pocket 1 7b while gradually shifting the tool towards the line of the pocket 1 7b to machine and form the pocket 1 7b. The tool is then returned to the starting point P 1 to turn to the machining of the protrusion 1 7a.
Namely, as shown in Fig. 4b, the tool 1 6 is moved along the paths similar to the profile of the protrusion 1 7a while being gradually shifted towards the protrusion 1 7a thereby to complete the machining of the pocket 1 7b having the central protrusion 1 7a.
It is conceivable that an air-cut or incomplete cutting of the pocket wall takes place when the cutting operation is switched from the cutting of the pocket 1 7b to the cutting of the protrusion 1 7a. In order to avoid such a problem, a correcting operation is made for a while after restarting from the point P 1, i.e. after the commencement of the machining of the protrusion 1 7a, by modifying the tool path K similar to the profile of the protrusion 1 7a in conformity with the shape of the pocket 1 7b.
More specifically, this correction is made in the following manner. Assume here two tool paths: namely an innermost tool path K1 similar to the pocket 1 7b and a tool path K2 similar to the profile of the protrusion 1 7a. The tool 1 6 is moved along the path K2 only within the region in which the path K2 does not come out of the range of the path K1 and, in other regions, i.e. in the region in which the path K2 comes out of the path K1 ,the tool 16 is moved along the path K1.
Various other cutting patterns CPT constituting the machining patterns PAT are conceiveable than those mentioned hereinbefore. It will be clear to those skilled in the art that the invention can be carried out with any machining patterns PAT determined to correspond to each machining unit, irrespective of the kind of the cutting patterns CPT constituting the machining pattern CPT.
As has been described, machining patterns PAT corresponding to respective machining units are stored in the machining pattern memory 11 and, as a machining unit is inputted, the machining pattern PAT corresponding to the inputted machining unit is read out and, thereafter, the final tool path K is determined in accordance with the thus read out machining pattern PAT. Thus, the tool path is determined automatically simply through the inputting of necessary machining data DATA and so forth together with the selected machining unit by the operator.
It is thus possible to obtain a machining control method for milling which is improved to eliminate the necessity for the trouble of determination of the tool paths by the programmer or the operator.
Although the invention has been described through specific terms, it is to be noted that the described embodiment is only illustrative but not in the limiting sense.
It is to be noted also that the scope of the invention is not limited by the described embodiment but is limited solely by the appended

Claims (5)

claims. Claims
1. A machining control method for milling performed by a numerical control machine tool comprising: sorting the milling into a plurality of machining units in accordance with the machining shape, storing machining patterns corresponding to the machining units within a machining pattern memory, reading, when one of said machining units is inputted, the machining pattern corresponding to the inputted machining unit out of the machining pattern memory, and computing and determining the final tool path in accordance with the read out machining pattern.
2. A machining control method for milling performed by a numerical control machine tool according to claim 1, wherein the milling is sorted into a line machining mode and a surface machining mode, and each of said modes is classified into a plurality of machining units.
3. A machining control method for milling performed by a numerical control machine tool according to claim 2, wherein said line machining mode includes a line center machining unit, line right machining unit, line left machining unit, line outer machining unit, line inner machining unit, chamfer right machining unit, chamfer left machining unit, chamfer outer machining unit and a chamfer inner machining unit.
4. A machining control method for milling performed by a numerical control machine tool according to claim 2 or claim 3, wherein said surface machining mode includes a face mill machining unit, end mill surface machining unit, end mill crest machining unit, pocket end mill machining unit, pocket end mill crest machining unit, pocket end mill valley machining unit and an end mill groove machining unit.
5. A machining control method for milling performed by a numerical control machine load, as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.
GB08232632A 1981-11-25 1982-11-16 Machining control method for milling Expired GB2110425B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56188952A JPS5890439A (en) 1981-11-25 1981-11-25 Control method for milling process

Publications (2)

Publication Number Publication Date
GB2110425A true GB2110425A (en) 1983-06-15
GB2110425B GB2110425B (en) 1985-08-21

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GB08232632A Expired GB2110425B (en) 1981-11-25 1982-11-16 Machining control method for milling

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JP (1) JPS5890439A (en)
DE (1) DE3243708A1 (en)
FR (1) FR2516827B1 (en)
GB (1) GB2110425B (en)
IT (1) IT1191230B (en)

Cited By (2)

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US6676344B1 (en) * 1999-09-21 2004-01-13 Rolls Royce Plc Methods and apparatus for machining workpieces
WO2010025522A1 (en) * 2008-09-08 2010-03-11 Meat And Livestock Australia Limited An apparatus for use in breaking down an animal carcass

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JPS58155409A (en) * 1982-03-10 1983-09-16 Mitsubishi Electric Corp Numerical control working system
JPS6090653A (en) * 1983-10-22 1985-05-21 Fanuc Ltd Working for range
JPS60127953A (en) * 1983-12-14 1985-07-08 Fanuc Ltd Regional work
JPS60127952A (en) * 1983-12-14 1985-07-08 Fanuc Ltd Regional work
JPS60126710A (en) * 1983-12-14 1985-07-06 Fanuc Ltd Method for determining working process in automatic programming
JPS61103213A (en) * 1984-10-26 1986-05-21 Fanuc Ltd Production of numerical control data
JPH01180009A (en) * 1988-01-11 1989-07-18 Fanuc Ltd Automatic programming system
JPH02218539A (en) * 1989-02-14 1990-08-31 Fanuc Ltd Profile method
JPH03256654A (en) * 1990-03-02 1991-11-15 Fanuc Ltd Setting method for copying region
JP2879383B2 (en) * 1991-04-11 1999-04-05 三菱電機株式会社 Electric discharge machining method and apparatus
DE19614131A1 (en) * 1996-04-10 1997-10-23 Agie Ag Ind Elektronik Control of NC- or CNC-machine tool such as spark erosion machine
JP2010005715A (en) * 2008-06-25 2010-01-14 Mimaki Engineering Co Ltd Cutting plotter and cleaning method of cut chips using it
CN103586513B (en) * 2013-11-12 2015-08-26 中国南方航空工业(集团)有限公司 A kind of processing method of PRECISION HOLE of airplane turbine casing mounting edge
CN104772648A (en) * 2015-04-09 2015-07-15 西安工业大学 Milling processing method for thin-wall workpiece of airplane
CN104999121B (en) * 2015-08-07 2017-05-03 上海中船三井造船柴油机有限公司 Method and tool for machining rack guide plate

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GB2054199B (en) * 1979-06-14 1983-10-05 Daihatsu Motor Co Ltd Numerically controlled machine tool
JPS57189206A (en) * 1981-05-18 1982-11-20 Fanuc Ltd Numerical control system
JPS5877424A (en) * 1981-10-28 1983-05-10 Yamazaki Mazak Corp Tool selective control method for machining center

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6676344B1 (en) * 1999-09-21 2004-01-13 Rolls Royce Plc Methods and apparatus for machining workpieces
WO2010025522A1 (en) * 2008-09-08 2010-03-11 Meat And Livestock Australia Limited An apparatus for use in breaking down an animal carcass

Also Published As

Publication number Publication date
GB2110425B (en) 1985-08-21
IT8268338A0 (en) 1982-11-17
JPS5890439A (en) 1983-05-30
DE3243708A1 (en) 1983-06-01
FR2516827B1 (en) 1988-06-10
IT1191230B (en) 1988-02-24
JPH0367822B2 (en) 1991-10-24
FR2516827A1 (en) 1983-05-27

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Effective date: 19941116