EP0179940B1 - Procédé automatisé de fraisage chimique - Google Patents

Procédé automatisé de fraisage chimique Download PDF

Info

Publication number
EP0179940B1
EP0179940B1 EP19840113095 EP84113095A EP0179940B1 EP 0179940 B1 EP0179940 B1 EP 0179940B1 EP 19840113095 EP19840113095 EP 19840113095 EP 84113095 A EP84113095 A EP 84113095A EP 0179940 B1 EP0179940 B1 EP 0179940B1
Authority
EP
European Patent Office
Prior art keywords
chemical milling
metal
milling process
metals
automated chemical
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.)
Expired
Application number
EP19840113095
Other languages
German (de)
English (en)
Other versions
EP0179940A1 (fr
Inventor
Lawrence H. Org
Herbert R. Jaffee
Irwin Mitzelman
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.)
Grumman Corp
Original Assignee
Grumman Aerospace Corp
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 Grumman Aerospace Corp filed Critical Grumman Aerospace Corp
Priority to EP19840113095 priority Critical patent/EP0179940B1/fr
Priority to DE8484113095T priority patent/DE3474167D1/de
Publication of EP0179940A1 publication Critical patent/EP0179940A1/fr
Application granted granted Critical
Publication of EP0179940B1 publication Critical patent/EP0179940B1/fr
Expired legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F1/00—Etching metallic material by chemical means
    • C23F1/02—Local etching
    • C23F1/04—Chemical milling

Definitions

  • the field of the present invention relates to an improved automated method for chemically milling metal and metallic structures.
  • Chemical milling is widely employed in the aircraft and aerospace industries to remove excess metal from metal parts wherein the removed metal is not essential to the strength of the component part.
  • the chemical milling process normally employs a series of masking and metal removal steps.
  • the metal is removed by an etching or milling bath which may be either caustic or acid depending upon the metal or alloy being milled.
  • Chemical milling may be used to produce one piece structures having a skin and load bearing ribs or stiffeners that provide lightweight alternatives for traditional aircraft skin and stringer constructions.
  • Chemical milling is widely used to increase the strength to weight ratio of components parts in the aircraft airframe.
  • Chemical milling traditionally involves the steps of masking and chemically milling a metallic workpiece and may repeat the sequence several times to further alter the workpiece configuration.
  • U.S. Patent 4,137,118 discloses a method of chemically milling an efficient lightweight structure by removing excess metal to form the ribs and skin of an aircraft structure. The milling step is repeated to sequentially undercut and impart an "I” or "T” section to the ribs and to reduce the thickness of the skin.
  • U.S. Patent 3,745,079 discloses a method of chemically milling a titanium alloy stock for use as a structural member in an aircraft.
  • U.S. Patent 2,888,335 discloses a process of chemically milling a workpiece that sets forth a method of sequentially milling the workpiece with multiple cuts in the mask material to produce a plurality of milled levels in the workpiece. in between each etching bath, a portion of the mask is removed so that the final configuration has a milled pattern of varying depths throughout the workpiece.
  • U.S. Patent 3,380,863 discloses masking material for use in chemical milling having a styrene/butadiene block copolymer composition. This material is widely used in chemical milling processes for masking the part to be protected during the etching bath.
  • the prior art methods comprise the steps of marking the aluminum or titanium stock with a reference mark or tooling hole for conveying the stock through the etching solution.
  • the metal part is then covered or coated with the butadiene/styrene copolymer masking material.
  • a template is laid over the masking material and the masked material is handcut along the template line.
  • the masking material is then marked with a marking pen along the cut or scribe line.
  • the metal plate is then milled and rinsed in a counterflow rinse water.
  • the second mark are is removed, and the workpiece is reimmersed in the etching bath.
  • the workpiece is rinsed again and the process is repeated for the desired number of milling steps.
  • the workpiece is "de-smutting".
  • a typical "de-smutting" agent is disclosed in U.S. Patent 3,988,254.
  • the present invention involves the new use of two existing devices which have heretofore been used for other tasks.
  • U.S. Patent 3,555,950 discloses a device for automatically cutting a photomask for use in producing integrated circuits.
  • the aluminum foil is cut, and the plastic laminate material is retained to define an optically transparent negative for producing an integrated circuit board.
  • Computer controlled cutting means have been widely used in the garment industry for cutting one or more sheets of fabric to a desired pattern size. These devices also have drive motors for moving a cutting tool in x and y directions. Examples of computer operated cutting devices are disclosed in U.S. Patents 3,803,960, 3,805,650, 3,895,358, 3,991,636 and 4,171,657.
  • the tangentially controlled scribing tool is mounted on a robotic device that may be computer controlled through h the x, y, z dimensions to provide an accurate scribing depth as the robotic device traverses the three-dimensional contoured surface.
  • a robotic device that may be modified for use in the chemical milling process is manufactured by ASEA, Inc. and is described in the ASEA pamphlet YB 11-101 E.
  • An alternate mans of generating the instructions for controlling the movements of the robotic device or the flatbed drafting device is to create new template geometry on a CRT via an existing computer program that is currently sold under the "CADAM" tradename.
  • This program will define the x and y coordinate values of the newly created mask before they are digitized and stored on magnetic tape.
  • the present invention includes the steps of coating the metal that is to be milled with an etchant resistant mask, such as a styrene copolymer.
  • an etchant resistant mask such as a styrene copolymer.
  • the perimeter of the area to be chemically milled is then digitized to define a plurality of point definitions along the x, y axis of the flat metal stock, or through a set of x, y, z axes for three-dimensional workpieces. If more than one area is to be chemically milled in a sequential milling process, the values of all of the coordinates are defined and stored on a magnetic storage medium such as a magnetic tape, a disc drive or a bubble memory means.
  • the process includes the step of automatically scribing the metal and the coating with a scribing tool wherein the scribing tool cuts through the resist coating along the perimeter defined by the x, y coordinate values or by the x, y, z coordinate values on three-dimensional workpieces.
  • the cut lines are marked for visibility to assist the operator in removing areas of the resist coating prior to the milling step. If the workpiece is to be involved in a sequential milling operation, the sequential cut lines are recoated with a temporary sealant to prevent the entry of the etching bath into the scribe line.
  • the workpiece is immersed into an etching solution for a predetermined period of time to remove a predetermined amount of metal from the uncoated area(s).
  • the etching bath is neutralized with a counter-flow water bath. If sequential milling steps are involved the second resist coating covering the second area to be chemically milled is removed, and the partially coated metal is then reimmersed in the etching solution for a predetermined period of time. This series of steps is then completed until the workpiece has been milled to its final configuration. Following the final etching bath, the workpiece is then "de-smutted" to remove the layer of metallic residue left by the etching bath.
  • the present invention includes the digitizing of existing masks to form x, y coordinate values for each of the perimeter lines defined by an existing mask with respect to either two or three dimensional workpieces.
  • new template geometry may be created on a CRT connected to a CPU having the appropriate software.
  • One software program particularly appropriate for the creation of new template geometry is the CADAM software, a commercially available licensed software package.
  • the present invention uses an electronically controlled scribing tool that exerts a predetermined amount of pressure against a cutting knife which engages the resist coating and the base metal to be chemically milled.
  • the cutting pressure may be very carefully controlled to provide an even and accurate cutting depth through the resist coating and .001 inch (25.4 ⁇ l m) into the workpiece.
  • the present invention provides an automated chemical milling process for chemically milling metal or metallic parts.
  • the automated chemical milling process of the present invention is set forth in a diagrammatic flow chart.
  • the aluminum alloy or titanium alloy feed stock 11 is first cut to size for the part to be produced, or a series of parts when a plurality of parts are intended to be produced from a single piece of feed stock. If the feed stock is a flat stock, it then proceeds to the flow coating process 12 wherein it is flow coated with the styrene/butadiene copolymer resist mask sold under the brand name of "Turco Mask 522". "Turco" is currently available from Turco Products, Inc., Wilmington, California. If the feed stock is intended for use as a three-dimensional workpiece and is not provided as a three-dimensional feedstock, it then proceeds to a contouring or stamping step 13 wherein the flat feed stock is contoured to the desired three-dimensional configuration.
  • the mask cutting was accomplished by laying a template over the feed stock and marking the outline of the template on the feed stock. The marked outline is then handcut so as to cut through the resist coating and lightly score the surface of the metal workpiece. The desired depth of cut into the metal workpiece is .001 inches (25.4 11m). Current military specifications for use in aircraft intended for purchase by the United States Government prescribe a maximum cut into the workpiece of .004 inches (101.6 11m).
  • the subsequent milling step will, undercut the resist coating, and if the cut is not deep enough, it will cause a "blow- out" when the center portion of the template is removed for milling.
  • the "blow-out must then be retouched by hand, when is a time consuming, labor intensive operation.
  • the present invention automates the chemical milling processed by one of three separate beginning steps.
  • an existing template may be placed on top of the workpiece, and an optical scan mode of the template. All of the initial starting marks, the workpiece size, the template number and other desired information is keyed into memory along with the optical scan to provide the data necessary to align the cutting device at the appropriate point on the workpiece when the mask cutting operation 14 begins.
  • a stylus may be used to trace the outline of the template while each of the reference points along the template are keyed into memory via the CRT.
  • each of the straight lines could be keyed by placing the stencil at the corner and keying in the positional data and cut orientation. The stencil would then be moved to the end of that particular straight line and the second key point set of data would be entered.
  • next template describing the second area to be chemically milled would then be overlaid with respect to the initial reference marks, and it would be optically scanned, or traced with a stylus pencil to derive the key point data for the existing template.
  • the CPU 16 would be digitizing the x, y coordinate values of each of the key points entered at 15.
  • the digitizing step is indicated us a separate step 17 in Figure 1 inasmuch as a variety of methods for digitizing an existing template exist. Two methods for digitizing an existing template were set forth above, but is apparent to one skilled in the data processing art that a variety of methods could be used to define the x, y coordinate values and convert them to digital form for use in a conventional CPU 16.
  • a printout is produced as indicated at 18.
  • This printout may be done with a Kongsberg flatbed drafting table similar to the one that will be used with respect to the mask cutting operation 14 later on in the process.
  • the Kongsberg flatbed drafting table is currently available from "Kongsberg North America, Inc.”, 135 Fort Lee Road, Leonia, Jew Jersey 07605. Any printout device will work providing it is capable of generating a full size template that may be physically checked against the template that was entered via the optical scan or key data entry indicated at 15.
  • the entry of the x, y, z coordinate values for the robotic device is similar to that used for the digitizing of existing templates for flat feed stock.
  • the handcutting of the three-dimensional workpiece is even more difficult and time consuming than the cutting of a two-dimensional workpiece.
  • a constant pressure must be exerted to precisely track the contours of the workpiece to completely cut through the mask and light score the metal surface without causing any undercuts or blow-outs.
  • the "ASEA” robot is equipped with its own computer guidance system and is normally programmed by the "teach” method which uses a robotic tracking method of tracing the stencil with a stylus to "teach” the robot the desired contour to be followed.
  • the "ASEA” robot is currently available from “ASEA, Inc.”, 4 New King Street, White Plains, New York 10604.
  • the stencil attached to the robot is placed manually at the initial reference starting position, and that key point data is entered. This operation "teaches” the robot that this position is to be assumed with respect to programmed operation for all future beginning reference points.
  • the digital positioning values for all three axes and the required traverse speeds are then stored in the computer memory.
  • the reference point data is used as a simple way of obtaining coordinate transformation in straight line positioning for the robot.
  • the reference point entered by the key point data at 19 does not cause any robotic motion, it simply defines the first, second, third ... n, points of the pattern of movement to be traversed.
  • the distance and direction to the subsequent reference point is calculated between reference points and executed relative to the point in space at which the robot is situated before the next reference point is entered.
  • the robotic device is also equipped with a separate instruction function wherein the motor speed for each axes is selected so that all axes reach the new position simultaneously. This is particularly useful in following contours generated by a series of closely related key data points along a complex x, y, z coordinate curve.
  • the keypoint data from the robotic tracking of the existing template can be read out onto magnetic tape as indicated at 23 or any other form of permanent magnetic storage media.
  • the magnetic tape created for the part that is to be produced is read back into the robotic memory for execution of the three-dimensional template.
  • a third method of generating masks for the automated chemical milling process of the present invention is illustrated at 20 and 21 wherein new mask geometry is created on a CRT through the use of a program entitled "CADAM".
  • the CADAM program is a commercially available, licensed software program available through CADAM, Inc. in Burbank, California, or from IBM.
  • the part to be created is displayed on the CRT and a series of key points are entered along the part to define the new mask geometry.
  • the key points are then filled in by the operator at the CRT to completely enclose the perimeter of the new template geometry. If sequential milling baths are desired, each of the templates are generated by the operator at the CRT by entering the desired key points to define the x, y values of each of the points along the perimeter.
  • the new template geometry is digitized as it is created by the CPU 16, and, if desired, a printout may be generated as indicated at 18 to check the mask geometry against the feed stock example or an initial mock up of the part that may have been created in the model shop.
  • a separate nesting subroutine 22 is used to nest the various template perimeters in the most efficient manner for the particular size and configuration of the beginning feed stock.
  • the "nesting" subroutine indicated at 22 is a software program entitled “CAMSCO” and is available through CAMSCO, Inc., 1200 N. Bowser, Richardson, Texas 75081.
  • Instructions from CPU 25 to scribe control 26 utilizes only the x and y axes for flat feed stock.
  • one motor is used for the x axis and one motor is used for the y axis. These are the only two values that are digitized and used to control the positioning of the scribing tool.
  • the scribing tool is controlled by analog signal generated by the scribe control 26, as will be hereinafter described in detail.
  • the generation of the commands for the scribe control is substantially more complex.
  • the magnetic tape 23 created by the robotic device during the "teach" function may be reinserted into the CPU controlling the robotic device, and each of the rotational motions will be generated in the same sequence and order as they were "taught" to the device during the key point data step 19.
  • the robotic control indicated at 27 is the process of controlling the relative rotational axes of each of the motors in the robotic device.
  • the scribe controls indicated at 26 may be derived in the three-dimensional operating mode from the robotic control 27, or in the two-dimensional mode from the Kongsberg table 28.
  • Scribe control 26 is capable of effecting three separate operations on each of the pieces of feed stock 11 that are flow coated as indicated at 12. These three steps are the mask cutting indicated at 14, the marking step 29 and the resealing step indicated at 30.
  • the CPU 25 will drive the x, y motors of the Kongsberg table as indicated at 28, while the scribe control 26 regulates the pressure of the cutting knife and the orientation of the cutting blade during the mask cutting operation 14. Since the most is somewhat resilient, it is difficult to see the cut lines in the mask. Therefore, after the mask has been cut, it is conventional practice to mark the scribe line as indicated by 29 with a marker to assist the workmen who remove parts of the mask in finding the area to be removed.
  • the marking step while not absolutely essential, it is highly desirable to achieve error-free etching or chemical milling.
  • the scribe control 26 then recoats all but one of the template lines cut during the mask cutting operation 14. Normally, the innermost template is then removed as indicated at 32, and the workpiece is then immersed in the etching bath 31. If multiple masks and multiple milling steps are involved, the workpiece is recycled as indicated at 32a for the removal of the second mask and a return to the etching bath along 31a. After each of the areas have been milled on the workpiece, it is then de-smutted in a de-smutting bath 33 and sent to a router for part separation as indicated at 34.
  • the part separation step 34 may be used when a plurality of parts are nested on a single piece of feed stock, or when a portion of the feedstock is used for the positioning of the reference or alignment holes that guide the workpiece through the various manufacturing steps that it will encounter.
  • the tangentially controlled scribing tool uses a single knife 35 that is secured in a central barrel 36 by means of a set screw 37.
  • Barrel 36 is provided for both rotational and reciprocating movement by means of an air bearing 37 which completely surrounds torque piston 38.
  • the piston 38 is responsive to two orthogonal stator windings 39 and 40 which are in turn connected to sine 41 and cosine 42 analog voltages received from the scribe control 26 illustrated in Figure 1. These voltages turns the torque receiver piston 38, and subsequently the knife's leading edge to ensure that knife 35 always present its normal cutting edge to the material consistent with changes in the direction of the motion of the tool.
  • a third winding 43 is set by the operator through a potentiometer or other signal device 44 to control the downward pressure exerted by piston 38 on knife 35. The effect of this downward pressure will be hereinafter more fully described with respect to Figure 5.
  • the aluminum or titanium workpiece 11 has been greatly exaggerated in depth relative to the size of the tangential scribing tool to illustrate the relationship between the depth of the feed stock 11 a, and the depth of the flow coat mask 12a.
  • the aluminum or titanium work stock 11a ranges in thickness as illustrated by the arrows "A” from 1/8 of an inch (3.2 mm) to 1/2 an inch (12.7 mm) in thickness.
  • the thickness of the mask resist coating 12a, indicated by the arrows "B” in Figure 2 is approximately 10 mils (254 pm).
  • the reciprocal range of knife 35, indicated by the arrows "C” in Figure 2 is approximately 1/8 of an inch (3.2 mm).
  • the aluminum alloys are milled in a sodium hydroxide alkaline bath while the titanium alloys are milled in a hydrofluoric acid bath.
  • Other desired baths for aluminum may include caustic soda or potassium hydroxide, and another chemical bath that may be highly desirable for titanium is nitric/hydrofluoric acid.
  • a workpiece 11b has been subjected to a multiple etching bath. Multiple cuts were made at 14b, 14c and 14d through the protective mask to define separate masks 12a, 12b and 12c. After the cuts 14a-14d were made, cuts 14c and 14d were resealed with "TURCO" or the styrene/butadiene copolymer mask material as indicated at 30a and 30b.
  • the initial portion 12a was removed by hand as illustrated in Figure 4, and the first layer of metal was milled away as indicated by the dotted line surrounding 31 a. Following this initial milling, the sealant material 30a was removed, the cut mask material indicated at 12d was removed, and the workpiece was reinserted in the etchant bath. During the second immersion, the metal indicated at 31 b was removed by action of the etchant bath.
  • the curve illustrated in Figure 5 illustrates the depth expressed in inches (in brackets in um) of the cut by the knife blade 35 through the mask 12a and into the metal substrate 11a.
  • the horizontal axis labelled "force settings" are indicative of the signals provided by means 44 which originate from the scribe control 26 illustrated in Figure 1. While normally this is preset by the operator at the time the cuts are made in the mask, the signal could be supplied as part of the data processing signal stored on magnetic tape 23. As indicated by the slope of curve 45 and 46 the pressure generated by the torque piston 38 and winding 43 is sufficient to readily cut through the mask, but only lightly score the feed stock.
  • the maximum depth of cut through the aluminum feed stock was .002 inches (51 um) even at the highest "force setting" for the tangentially controlled scribing tool. This is well within the .004 inches (102 um) limit set by current military specifications. Inasmuch as the titanium feed stock is substantially harder than the aluminum feed stock, the depth of cut into the titanium is even less than the cut into the aluminum.
  • the scribe control step illustrated at 26 in Figure 1 is more fully illustrated in Figure 6 in the form of scribe control head 26a.
  • the scribe control head 26a is mounted on a Kongsberg Flatbed Drafting Table as illustrated in Figure 7. This particular drafting table may be extended in 1-1/2 meter sections up to a maximum length of 10.5 meters.
  • the scribe control 26a is carried by a gantry 50 for movements along the x axis and by carriage means 51 and 52 which reciprocate along guide rails 53 and 54 (not shown) mounted on either side of the flatbed drafting table.
  • a pair of high performance dc servo motors provide for precise x, y positioning of the scribe control 26a by means of rack and pinion drive mechanisms.
  • a plurality of air pressurizing means 59, 60 and 61 pressurize the containers of sealant 57 and ink containers (not shown). The inks are then dispensed to marking pens 55 and 56 by means of tubes 62 and 63 for marking the cut lines after the tangentially controlled cutting tool 14a has cut through the mask.
  • Electronic control for the scribing tool is maintained through an overhead cable 64 illustrated in Figure 7 to the scribe control 26a.
  • Electronic control of each of the cutting, marking and resealing stages is provided by means of connector 65 and control line 66.
  • the air supply for the tangentially controlled cutting tools air bearing is provided through conduit 67 while conduit 68 provides a similar supply for the ball applicator means 30a used in resealing the cut scribe lines.
  • Kongsberg Flatbed Drafting Table illustrated in Figure 7 is capable of a relatively high rate of movement in the x and y axes, it normally does so only on straight cuts.
  • the software provided for the Kongsberg table at 28 in Figure 1 provides the CPU 25 with a "look ahead" feature that enables the CPU to look ahead at the next block of instructions and slow the scribing tool 26a when a change in direction is indicated. For example, if the device is in the mask cutting mode, with the tangentially controlled scribing tool cutting through the mask cut material 12a, any change in angle for the knife blade 35 of more than 7° results in a vertical reciprocation of the piston 38 illustrated in Figure 2.
  • the reciprocal cutting feature of this device enables the operator of the device to insert a very narrow knife point for blade 35 and to cut holes in the mask material of very small diameter.
  • a round circular hole as small as 1/4 of an inch in diameter may be smoothly cut in the mask material with the present invention. Cuts of this size radius have been heretofore impossible with a handcutting operation.
  • the present invention makes possible high speed scribing with high precision and repeatability. As indicated previously, one workpiece three-feet by four-feet with multiple parts that took 6 to 8 hours to handscribe and mark by hand took 11 minutes to scribe and mark with the present invention.
  • the present invention also makes possible the application of the scribe control 26a to three-dimensional workpieces as illustrated in Figures 8-10.
  • the scribe control 26a is mounted on a robotic device 60 for cutting, marking and masking the interior of a workpiece as illustrated in Figure 8.
  • the master mold 70 has thereon a workpiece 11f that has been preshaped to a three-dimensional contour.
  • the workpiece 11f has also been coated with coating 12a and is ready for cutting, marking and resealing as was previously described with respect to Figure 2-4.
  • the robotic device 60 is equipped with a plurality of rotational axes, each of which assists the device in transporting the scribe control 26a from one point on the x, y, z axes to a second point on the x, y, z axes.
  • the pedestal 71 rotates about a pedestal turning moment 72 which is described as (p.
  • the second robotic motion is the in and out moment of the lower arm 72 and is described by the angle 8.
  • the third rotational axes prescribes the up and down motion of arm 73 about the angle y.
  • the robot may also be equipped with three separate motions for the wrist, although only two are illustrated in Figure 8.
  • the first wrist moment is a which is referred to as a "wrist bend", and a second rotational axis ⁇ which is indicated as a wrist turn.
  • These five rotational axes make it possible for the robot to traverse from any x, y, z coordinate point to the next x, y, z coordinate point.
  • each of the servo motors responsible for moving the robot about each of the five axes illustrated in Figure 8 may be programmed to run simultaneously so that all axes start at the same time and run at the same motor speed. Each motor then stops when the part it drives has reached its new programmed position.
  • the robotic device manufactured by "ASEA" has an instruction function that will provide a motor speed for each axes to be selected so that all axes reach the new programmed position simultaneously.
  • This provides for smooth contouring of three-dimensional work surfaces when the robot is traversing a curve through three-dimensinal space.
  • the tangentially controlled scribing tool exerts a constant downward pressure on the scribing knife throughout a reciprocal range of 1/8 of an inch (3.2 mm).
  • This reciprocal movement of the knife provides that the knife remains in a constant force engagement with the aluminum or titanium workpiece throughout the various movements of the robot's arms.
  • the robot has a positional tolerance for all five axes of ⁇ .004 mm which is compensated for by the air bearing reciprocal tolerance of 1/8 of an inch (3.2 mm) as indicated at "C" in Figure 2.
  • Figure 9 illustrates the traditional x, y, z axes normally used to span three-dimensional space.
  • Afourth axis y is illustrated to note that any set of x, y, z axes could be used, provided that no two axes are parallel to one another. If a particular set of x, y, z axes is more efficient in calculating the movement through three-dimensional space with respect to a given surface part configuration, then the x, y, z axes for that particular part may be altered to provide for more efficient calculation of the movements from one x, y, z point coordinate value to another.
  • Figure 10 is an illustration of a part of an aircraft that has been chemically milled after the mask was cut by a robotic device as illustrated in Figure 8.
  • the aircraft skin 81 remains coated with the resist material on its lower surface throughout the entire milling operation.
  • the ribs 82, 83 and 84 and stringers 85, 86, 87 and 88 are integrally formed with the skin 81 to provide a unitary structure that is lightweight, strong and free from any mechanical joints, rivets, screws or other fastening devices.
  • the natural undercutting action of the chemical milling process will provide a natural "T" or "I-beam" configuration for strengthening the metal skin 81.
  • Figure 11 illustrates one further advantage of the present invention.
  • the metal part 11g has defined thereon a template outline that has been cut and marked along 14a, 29a as illustrated in Figure 1.
  • a pair of tooling holes 90 and 91 have been defined within the chemically milled areas for gripping the part as it traverses through the various manufacturing steps that it will encounter.
  • the part 11g is covered with a mask material 12a outside the perimeter line defined by 14a, 29a.
  • the perimeter line 14a, 29a defined on part 11g is typical of a part configuration that might be formed.
  • An optional method for providing tooling holes is illustrated in the phantom lines for part 11 h and tooling holes 92 and 93.
  • the present invention eliminates tedious handscribing of the mask on flat and three-dimensional parts intended for chemical milling. It may eliminate the construction of new templates for new parts that are to be manufactured and will eliminate the use of existing templates for parts that have already been designed. It eliminates the handmarking of multiple scribed areas and cuts and eliminates the hand application ofTURCO sealer on the cuts to be used in sequential milling of the part. It provides a controlled depth of cut through the mask into the metal part that is very precise. The cutting can be conducted at high speeds with high precision and high repeatability.
  • the tangentially controlled scribing tool makes it possible to cut curves on both flat and three-dimensional surfaces and to define holes and curves that have not heretofore been previously possible with handscribed operations.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • ing And Chemical Polishing (AREA)

Claims (14)

1. Procédé d'usinage chimique automatisé pour métaux, ledit procédé comprenant les phases consistant à:
(a) enduire en (12) le métal qu'il s'agit d'usiner chimiquement d'un enduit de réserve;
(b) numériser en (17) la zone ou les zones à usiner chimiquement, pour définir au moins des valeurs de coordonnées x et y pour le périmètre de la zone ou des zones à usiner chimiquement;
(c) tracer automatiquement en (25, 26) le métal et l'enduit à l'aide d'un outil à tracer (14), ledit outil à tracer entaillant ledit enduite le long du périmètre défini par les valeurs de coordonnées x et y;
(d) enlever en (32) l'enduit de réserve de la zone ou des zones à usiner chimiquement; et
(e) immerger ledit métal partiellement enduit dans une solution d'attaque (31) pendant un temps prédéterminé pour éliminer une quantité prédéterminée de métal de la zone ou des zones non enduites.
2. Procédé d'usinage chimique automatisé pour métaux selon la revendication 1, caractérisé en ce que la phase (b) s'effectue
en definissant un espace tridimensionnel selon trois axes séparés x, y et z, dans lequel il n'y a pas deux axes parallèle entre eux et
en numérisant en (17) le zone ou les zones à usiner chimiquement avec des valeurs de coordonnées de point x, y et z; et en ce que la phase (c) s'effectue
en traçant en (26, 27) l'enduit et le métal le long d'un ou de plusieurs périmètres tridimensionnel(s) défini(s) par lesdites valeurs de coordonnées de point x, y et z.
3. Procédé d'usinage chimique automatisé pour des pièces métalliques tridimensionnelles selon la revendication 2, caractérisé en ce qu'il comprend en outre les phases consistant à définir trois ou plus de trois axes de rotation (26b) pour l'outil de traçage, ledit outil de traçage sélectionnant un ou plusieurs desdits axes de rotation en parcourant ledit espace tridimensionnel défini par lesdites valeurs de coordonnées x, y et z.
4. Procédé d'usinage chimique automatisé selon la revendication 1, 2 ou 3, caractérisé en ce que la phase (c) s'effectue en supplément
en traçant séparément en (14b, 14c, 14d) plus d'une seule zone à usiner chimiquement pour chaque pièce métallique, et
en réenduisant les lignes tracées par incision (30a, 30b) pour toutes les zones à usiner chimiquement sauf une, et en ce que les phases (d) et (e) s'effectuent
en elevant séquentiellement en (12a) l'enduit de réserve de chacune des zones à usiner chimiquement entre deux immersions additionnelles séparés dans ladite solution d'attaque;
de sorte que chacune des zones définies à uniser chimiquement est immergée dans ladite solution pendant des périodes cumulatives différentes.
5. Procédé d'usinage chimique automatisé pour métaux selon la revendication 1, 2 ou 3, caractérisé en u qu'il comprend en outre la phase consistant à marquer le ou les périmètre(s) de la zone ou des zones incisée(s) par ledit outil de traçage au moyen d'un marquer visible, ledit marquer marquant ledit enduit le long de la ligne ou des lignes de périmètre définie(s) par les valeurs de coordonnées x, y, ledit marquage se produisent avant que l'enduit de réserve n'ait été enlevé.
6. Procédé d'usinage chimique automatisé pour métaux selon la revendication 4, caractérisé en ce que la phase de réenduction utilise un mastic visible pour refermer et marquer simultanément les lignes de traçage incisées.
7. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 5, caractérisé en ce qu'il comprend en outre la phase consistant à mettre en série en (12a, 12d, 12e, 12b) les lignes de périmètre de chacune des zones à usiner chimiquement lorsque plus d'une seule pièce doit être usinée chimiquement à partir d'une seule et même plaque métallique.
8. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 6, caractérisé en ce qu'il comprend en outre la phase consistant à appliquer une force constante prédéterminée à l'outil de traçage (35) pour mettre à force ledit outil de traçage en prise avec ladite partie métallique (11a), ladite force étant appliquée perpendiculairement à un plan défini par au moins deux valeurs ponctuelles pour chaque point parcouru par ledit outil de traçage.
9. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 8, caractérisé en ce qu'il comprend en outre te traçage et l'usinage chimique de marques de repérage ((90, 91) dans une plaque métallique.
10. Procédé d'usinage chimique automatisé pour métaux selon la revendication 9, caractérisé en ce qu'on forme ensuite à partir desdites marques de repérage des trous d'outillage (90, 91).
11. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 6, caractérisé en ce qu'il comprend en outre la phase consistant à relever l'outil de traçage chaque fois qu'une ligne ou courbe décrite par un jeu futur de valeurs de coordonnées de points s'écarte de plus de 7° d'une ligne courbe tracée à partir d'une jeu précédent de valeurs de coordonnées de points.
12. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 11, caractérisé en ce que le métal (11) est l'aluminium ou ses alliages et le bain d'attaque (31) est un hydroxide de métal alcalin.
13. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 11, caractérisé en ce que le métal (11) est le titane ou ses alliages et le bain d'attaque (31) est un acide hydrohallogéné.
14. Procédé d'usinage chimique automatisé pour métaux selon l'une des revendications 1 à 13, caractérisé en ce que ledit enduit de réserve est un copolymère butadiène/styrène.
EP19840113095 1984-10-31 1984-10-31 Procédé automatisé de fraisage chimique Expired EP0179940B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP19840113095 EP0179940B1 (fr) 1984-10-31 1984-10-31 Procédé automatisé de fraisage chimique
DE8484113095T DE3474167D1 (en) 1984-10-31 1984-10-31 An automated chemical milling process

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19840113095 EP0179940B1 (fr) 1984-10-31 1984-10-31 Procédé automatisé de fraisage chimique

Publications (2)

Publication Number Publication Date
EP0179940A1 EP0179940A1 (fr) 1986-05-07
EP0179940B1 true EP0179940B1 (fr) 1988-09-21

Family

ID=8192257

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19840113095 Expired EP0179940B1 (fr) 1984-10-31 1984-10-31 Procédé automatisé de fraisage chimique

Country Status (2)

Country Link
EP (1) EP0179940B1 (fr)
DE (1) DE3474167D1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999028535A1 (fr) * 1997-11-28 1999-06-10 Gravutex Eschmann International Limited Procede de gravure
US8778202B2 (en) 2011-09-23 2014-07-15 Kings Mountain International, Inc. Spreading ink over a press plate using a heater
CN102912347A (zh) * 2012-10-22 2013-02-06 邹华兵 超精密化学铣镀加工刀具
CN106541418B (zh) * 2015-09-16 2019-11-19 中国科学院宁波材料技术与工程研究所 末端执行器及工业机器人
US10563309B1 (en) 2015-10-13 2020-02-18 Kings Mountain International, Inc. Method for creating a textured press plate

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4364110A (en) * 1970-12-28 1982-12-14 Hyatt Gilbert P Computerized machine control system
US4120583A (en) * 1970-12-28 1978-10-17 Hyatt Gilbert P High registration photomask method and apparatus
US4370720A (en) * 1970-12-28 1983-01-25 Hyatt Gilbert P Coordinate rotation for numerical control system
US4371923A (en) * 1970-12-28 1983-02-01 Hyatt Gilbert P Computer system architecture
DE2234674B2 (de) * 1972-07-14 1976-01-02 Stumpf, Guenter, 7421 Mehrstetten Steuermuster-Vorlage für eine durch eine Fotozellen-Abtasteinrichtung gesteuerte Koordinaten-Schneidmaschine
US3803960A (en) * 1972-12-11 1974-04-16 Gerber Garment Technology Inc System and method for cutting pattern pieces from sheet material
JPS5280901A (en) * 1975-12-26 1977-07-07 Yoshio Inoue Apparatus for drawing required contour line of image
US4113549A (en) * 1977-04-06 1978-09-12 Chem-Tronics, Inc. Chemical milling process
US4340166A (en) * 1978-11-22 1982-07-20 Kulicke & Soffa Industries, Inc. High speed wire bonding method
JPS5971515A (ja) * 1982-10-16 1984-04-23 Fanuc Ltd グラフィックディスプレイ装置

Also Published As

Publication number Publication date
EP0179940A1 (fr) 1986-05-07
DE3474167D1 (en) 1988-10-27

Similar Documents

Publication Publication Date Title
US4585519A (en) Automated chemical milling process
WO2005072903A2 (fr) Procede d'assemblage d'un article a l'aide d'une projection de lumiere laser et d'un materiau photoreactif
JP3670700B2 (ja) ロボット機構制御方法
US5208995A (en) Fixture gauge and method of manufacturing same
US20020095236A1 (en) Computer-produced carved signs and method and apparatus for making same
CN103713576B (zh) 多轴铣削加工工件表面形貌建模方法
US12055918B2 (en) System and method for automated precision control of a computer numerical control (CNC) machine
CN102091967A (zh) 一种多轴数控加工的进给速度平滑方法
EP0179940B1 (fr) Procédé automatisé de fraisage chimique
CN106647631A (zh) 龙门制孔机床加工碰撞检测分析方法
CN108068122A (zh) 一种大型船舶槽面加工装置及定位方法
CN114578754A (zh) 一种数控机床俯仰误差及偏摆误差辨识方法
CA1225312A (fr) Usinage chimique automatise
CN114739290B (zh) 线激光扫描化铣胶刻线的路径规划方法及系统
JPS61133384A (ja) 自動蝕刻方法
CN114905278B (zh) 金属增材制造打印件智能去支撑结构的装置以及方法
JPS6319280B2 (fr)
CN102566509B (zh) 基于包络理论的数控加工仿真中通用刀具扫描体生成方法
JP2004021954A (ja) Ｎｃデータの工具軌跡表示方法
NO169666B (no) Fremgangsmaate ved kjemisk fresing av metaller
JP2005063074A (ja) 曲面加工方法および装置ならびに光学素子
US7209802B2 (en) Method for controlling a robot
CN113945152B (zh) 利用立体块恢复单线结构光三维传感器测量功能的方法
JP2741518B2 (ja) ワークの寸法検査方法
CN112846323B (zh) 三维振动辅助铣削加工系统及结构型表面三维振动辅助铣削方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE FR GB LI NL SE

17P Request for examination filed

Effective date: 19860724

17Q First examination report despatched

Effective date: 19870706

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE FR GB LI NL SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19880921

Ref country code: CH

Effective date: 19880921

REF Corresponds to:

Ref document number: 3474167

Country of ref document: DE

Date of ref document: 19881027

ET Fr: translation filed
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19921005

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19921014

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19921021

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19921031

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19921110

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19931031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19931101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19940501

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19931031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19940630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19940701

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

EUG Se: european patent has lapsed

Ref document number: 84113095.8

Effective date: 19940610