US3384567A - Electrolyte guide member - Google Patents

Electrolyte guide member Download PDF

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Publication number
US3384567A
US3384567A US501643A US50164365A US3384567A US 3384567 A US3384567 A US 3384567A US 501643 A US501643 A US 501643A US 50164365 A US50164365 A US 50164365A US 3384567 A US3384567 A US 3384567A
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United States
Prior art keywords
tube
guide member
electrolyte
capillary
workpiece
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 - Lifetime
Application number
US501643A
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English (en)
Inventor
James D Andrews
Walter C Kunz
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.)
General Electric Co
Original Assignee
General Electric Co
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 General Electric Co filed Critical General Electric Co
Priority to US501643A priority Critical patent/US3384567A/en
Priority to GB24446/66A priority patent/GB1147952A/en
Priority to SE07650/66A priority patent/SE333438B/xx
Priority to NL666608162A priority patent/NL150406B/xx
Priority to FR65654A priority patent/FR1483524A/fr
Priority to CH1017866A priority patent/CH475363A/de
Priority to DE1565553A priority patent/DE1565553C3/de
Priority to US761352*A priority patent/US3489544A/en
Priority to US766005*A priority patent/US3556758A/en
Priority to BE712508D priority patent/BE712508A/xx
Application granted granted Critical
Publication of US3384567A publication Critical patent/US3384567A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00—Re-forming shaped glass
    • C03B23/04—Re-forming tubes or rods
    • C03B23/047—Re-forming tubes or rods by drawing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
    • B23H9/00—Machining specially adapted for treating particular metal objects or for obtaining special effects or results on metal objects
    • B23H9/14—Making holes
    • B23H9/16—Making holes using an electrolytic jet

Definitions

  • This invention relates to electrolytic material removal and, more particularly, to a guide member for directing electrolyte toward a workpiece and to a method and apparatus for making such member.
  • the electrolytic material removal process involves a cathodic tool which cooperates with an anodic workpiece through an electrolyte contacting both the tool and the workpiece. As electric current is made to flow through the electrolyte, material is removed to deplated from the electrically conductive workpiece.
  • One form of the electrolytic material removal process is more fully described in copending application Ser. No. 474,833, filed July 26, 1965 and assigned to the assignee of the present invention. This method form involves projecting a continuous stream of cathodically charged electrolyte toward an anodic workpiece to remove relatively small, selected portions of the workpiece material.
  • This form can be used to produce very small diameter cavities, slots or holes in a workpiece because the cathode which charges the electrolyte can be maintained external to the workpiece. Therefore, only the cathodically charged electrolyte need be guided appropriately toward the workpiece under proper conditions to allow electrolytic material removal to pro ceed.
  • an electrolyte guide means or member comprises a capillary tube made of an electrical non-conductor such as glass.
  • the material is drawn or formed into a nozzle having a capillary end portion.
  • a principal object of this invention is to provide an improved method for producing accurate and uniform members to guide cathodically charged electrolyte toward an anodic workpiece for use in an electrolytic ma terial removal process.
  • Another object is to provide an improved apparatus for producing such accurately dimensioned electrolyte guide members.
  • Still a further object is to provide an improved guide member having an outside diameter of less than about 0.06 and of specific shape and wall thickness to provide improved and efficient operation.
  • FIG. 1 is a fragmentary sectional view of the electrolyte guide member in which a cathode has been placed;
  • FIG. 2 is a partially diagrammatic representation of the apparatus of the present invention prior to operation
  • FIGS. 3 and 4 are views of a portion of the apparatus of FIG. 2 at various stages of operation;
  • FIG. 5 is a view of a modified form of the apparatus of "ice FIG. 2 including means to cut the guide member to an appropriate length;
  • FIG. 6 is a fragmentary sectional view of a glass tube before drawing
  • FIG. 7 is a fragmentary sectional View of a guide member drawn from the tube of FIG. 6;
  • FIG. 8 is a partially sectional view of a guide member particularly shaped for producing a side branch in an existing hole.
  • FIG. 9 is a graphical presentation of typical calibration data for two types of apparatus.
  • the electrolyte guide member of the present invention in one form is a dielectric hollow member having walls which define a small bore or capillary portion at one end terminating in a working tip.
  • the capillary portion has a wall thickness of no more than about 0.0020" and is of a length sufiicient to penetrate a desired distance into or through the workpiece.
  • the capillary portion has an inside diameter sufficiently large to provide an electrolyte stream capable of producing the size cavity desired. Its outside diameter is selected to allow electrolyte to flow from the cavity being produced. If the outside diameter is greater than about 0.06", the process in which this member is used is less efficient than other material removal methods. However, when the wall thickness of such a capillary portion is greater than 0.0020", the metal removal rate is greatly reduced.
  • a body portion of larger overall dimensions and which can act as an electrolyte reservoir joins the capillary portion through a transition section generally of varying wall thickness.
  • the transition section together with the capillary portion are sometimes referred to in this specification as the nozzle.
  • the guide member includes a capillary portion of 0.06" or less outside diameter with the wall thickness of 0.0020" or less.
  • the starting material used in the improved method of making the guide member is a hollow tube of a dielectric material, such as a supercooled liquid which is solid at room temperature.
  • the material most frequently used in the evaluation of this invention is a tube of a borosilicate type .of glass.
  • the tube is rotated while there is applied a tube stretching force, preferably of fixed magnitude, axially along the tube.
  • the tube stretching force is less than that force which will produce plastic deformation in the tube at room temperature.
  • a selected portion of the tube is heated at a first heating rate to soften that portion sufficiently to allow the tube stretching force to elongate the tube to a first axial length.
  • the elongation of the tube results in the formation of a necked-down or double nozzle area at the area of heat application between the ends of the tubes.
  • the selected portion of the tube can be heated at a second heating rate which is less than the first heating rate.
  • the second heating rate slows the rate of elongation to more accurately control further lengthening of the reduced area portion of the tube.
  • a capillary portion thus produced between the two ends of the tube is joined with the remainder of the tube through a pair of transition sections, one on each end of the capillary portion. If only one of the transition sections or portions was heated, the transition sections will not be of the same shape. In such case, the one which joins that portion of the tube to which the tube stretching force was applied generally is less desirable.
  • the capillary poition is cut at a selected point and the undesirable transition section and attached tube is then discarded.
  • the remaining portion including a capillary end portion joined to the remainder of the tube through a transition portion is an electrolyte guide member, the original tube end and the nozzle end of which can be trimmed further to a desired length.
  • the improved apparatus which can be used in the practice of the above method includes tube holding means, means to apply a tube stretching force to the tube, means to rotate the tube, sensing means to measure the length of the tube and heating means, responsive to the sensing means, capable of applying a plurality of heating conditions to a selected portion of the tube between the ends of the tube.
  • the improved electrolyte guide member shown generally at 2% in FIG. 1 includes a capillary portion 22 joined with a body portion 24 larger in dimensions and internal volume by a transition section 26. Because in this example the capillary portion is made integral with the body portion in accordance with the method of this invention, the transition section is funnel-shaped. Capillary portion 22 includes working tip 28 the walls of which define an opening 30 from which charged electrolyte is emitted in a stream toward the workpiece. Within body portion 24 can be included a cathode 32 such as in the form of the metal tube shown in FIG. 1. The capillary portion 22 has a wall thickness W of 0.0020" or less.
  • the capillary portion C is of a length sufiicient to give direction to an electrolyte which is charged by passing over cathode 32 and is of sufiicient length to penetrate a required distance into a workpiece or through a workpiece if such type of operation is planned.
  • the transition section generally has an axial length T which is at least 0.15 in order to allow for a smooth transition from the body portion 24 to the capillary portion 22.
  • the method aspect of the present invention by which the electrolyte guide member of FIG. 1 is made assures uniformity of wall thickness and the uniform circular cross section of the capillary portion. This controlled geometry assures repeatability of the size and shape of the cavity to be produced. Uniformity of guide members, one to the other, in the production of such articles as plates through which plastic filaments are drawn is significant to the quality of the final product.
  • a tube 34 of a dielectric material such as glass is rotated by a rotatable tube holding means such as chuck 36 driven by motor 38.
  • the rotation of motor 38 is initiated by switch 40 controlling the flow of power from a power source, not shown,
  • switch 40 controlling the flow of power from a power source, not shown.
  • a tube stretching force of a magnitude less than that which will produce plastic deformation of t the tube at room temperatureis applied to one end of the tube 34 such as by weight 42 clamped to one end of the tube prior to the start of rotation.
  • a heating means such as a tube furnace 44 which in FIGS. 2-5 is hollow and through which the tube projects, is positioned to heat a selectedportion of the tube from which the transition section 26 and capillary portion 22 shown in FIG. 1 are to be formed.
  • Switch 41 initiates current flow to the furnace.
  • the selected portion of the tube can be subjected to a variety of heating conditions through the use of variable transformer 45 controlling power to furnace 44. This controls elongation of the necked-down portion 22 in FIG. 3 which results from a combination of tube stretching force 42 and the heat applied from the heating means or furnace.
  • the heating means 44 is responsive to the total amount of elongation of tube 34. For example, as weight 42 passes between light source 48 and photosensitive element 50, which together form an electric eye mechanism, light beam 52 is broken.
  • tube 34 continues to elongate in capillary portion 22 and transition section 26.
  • the elongation is at a slower rate because resistance 46 reduces the rate of heat applied by means or furnace 44.
  • Elongation continues until.
  • a second light beam 50 shown in FIG. 3 between elements 62 and 64 of a second electric eye is broken as shown in FIG. 4. This causes solenoid 66 to break contact with connection 68 turning off heating means 44.
  • Rotating capillary portion 22 in FIG. 5 continues to elongate until its temperature falls below that point at which tube stretching force or weight 42 no longer can produce plastic deformation of the tube material.
  • the capillary portion 22 can then be cut while still held in rotating chuck 36 by a cutting means such as a glass scoring tool mounted in a holder 70. This separates portion 22a from 22b. Portion 22b and its attached transition and tube portion is then discarded and portion 22a with its associated transition and tube portion is removed from the holding means 36. Portion 22a which is the electrolyte guide member of the present invention, can be further sized as desired for use. By adjusting the amount and duration of heat applied for each selected tube size, the dimensions of electrolyte guide members can be closely controlled.
  • FIGS. 2 through 5 The accurate use of the apparatus shown in FIGS. 2 through 5 depends on the apparatus being calibrated for each size tubing used. Calibration includes understanding results from variation in conditions such as furnace temperature, furnace size, spacing between electric eye centers which controls heating rates, tube stretching force, and the like.
  • a summary of typical calibration data for two sets of conditions tested is shown in FIG. 9.
  • a weight of 0.05 pound to act as a tube stretching force was secured to the tubing at a point above the upper electric eye centerline shown as 52 in the drawing.
  • the tube was rotated at a speed of about 10 r.p.m. under the conditions listed in FIG. 9.
  • Example 1 In one typical statistical evaluation of the quality and reproducibility of guide members, 82 of such members were made and studied.
  • the tubing used was 0.1197 OD. x 0.083 I.D. Kimble KG 33 borosilicate glass having a strain or softening point of 515 C.
  • the aim was to produce a capillary portion in the range of 0.0054"i0.0002" LB. with a wall thickness of 0.0020" or less.
  • all of the 82 members were within these limits. From a statistical or quality control viewpoint this is within six sigma limits which means that in at least 99.7% of the cases, the member will fall within the desired limits.
  • the furnace used in this example was a tube furnace heated by 5 turns of #18 B&S gage uncovered Ni-Cr wire.
  • the first heating rate was for 1 min. 20 sec. at 15.7 amps and the second heating rate was 22 seconds at 13.5 amps.
  • the voltage was 10 volts and the tube was rotating at 10 rpm.
  • a critical feature of the guide member of the present invention is that the wall thickness shown as W in FIG. 1 is maintained at 0.0020 or less.
  • the walls of the capillary 'portion 22 of the guide member are required to direct a stream of charged electrolyte from a cathode 32 through opening 30 in working tip 28 toward the workpiece.
  • the walls of the capillary portion become an obstruction to the flow of electrolyte out of the cavity being produced. Therefore, the rate at which the electrolyte guide member is fed toward and into the workpiece depends upon the rate at which the cavity is being produced to allow electrolyte to flow into and out of the cavity in the workpiece. It has been recognized unexpectedly that if the wall thickness of the capillary portion is greater than about 0.0020" the feed rate must be reduced by about half in order to produce a desired cavity. The following example will more clearly illustrate this unusual occurrence.
  • Example 2 A nickel base superalloy having a nominal composition, by weight, of 15% Cr; 3.25% Ti; 0.025% B; 4.25% Al; 17% Co; 5% Mo; 0.015% (max) C with the balance nickel and incidental impurities wa used as a workpiece in an electrolytic material removal process through which it was desired to produce a hole having a diameter of about 0.033".
  • An electrolyte guide member of the type shown in FIG. 1 was made so that the capillary portion 22 had a length C of 0.600" with an opening diameter 30 of 0.020" and a wall thickness of 0.0025.
  • the ratio of the inside diameter to the outside diameter in the capillary portion of the tube 22 of the nozzle closely approximates the ratio of the inside diameter to the outside diameter of the raw tubing. This similarity makes it possible to predict the wall thickness in the drawn portion of the nozzle for a given tube size.
  • Tubing of a particular outside diameter can be preselected r can be prepared such as by centerless grinding to produce a given wall thickness in the finished capillary portion.
  • raw tubing as shown at 72 in FIG. 6 can be ground or otherwise reduced in outside diameter at a portion 74 so that a guide member as shown in FIG. 7 of a selected wall thickness and size can be produced according to the method of the present invention.
  • the guide member of the present invention can be used to produce cavities or holes through the side wall of larger holes or depressions in a workpiece such as is shown in FIG. 8 by bending the capillary portion of the guide member to direct the working tip 30 of the capillary portion 22 at a side wall 76 of workpiece 80.
  • An electrolyte guide member for use in electrolytic material removal to direct a stream of charged electrolyte toward a workpiece, the guide member including:
  • the capillary portion having an outside diameter of no greater than 0.06" and a maximum wall thickness of 00020", a hollow body portion of a dielectric material having an inside diameter substantially greater than that of said capillary and joined to said body portion through an intermediate, funnel shaped transition portion, and an electrode extending into said hollow body adapted to be connected to an electrical source.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
  • Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
US501643A 1965-10-22 1965-10-22 Electrolyte guide member Expired - Lifetime US3384567A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US501643A US3384567A (en) 1965-10-22 1965-10-22 Electrolyte guide member
GB24446/66A GB1147952A (en) 1965-10-22 1966-06-01 Improvements in electrolyte guide member and method and apparatus for making
SE07650/66A SE333438B (de) 1965-10-22 1966-06-03
NL666608162A NL150406B (nl) 1965-10-22 1966-06-13 Werkwijze voor de vervaardiging van een lichaam, dat bestaat uit een glazen buis, waarvan een eindgedeelte is uitgetrokken tot een capillair en inrichting voor het uitvoeren van deze werkwijze.
FR65654A FR1483524A (fr) 1965-10-22 1966-06-15 Organe de guidage pour électrolyte, et procédé et appareil pour la réalisation dudit organe
CH1017866A CH475363A (de) 1965-10-22 1966-07-13 Vorrichtung zum Führen einer elektrolytischen Flüssigkeit bei der elektrolytischen Metallbearbeitung sowie ein Verfahren zu deren Herstellung
DE1565553A DE1565553C3 (de) 1965-10-22 1966-07-21 Verfahren und Vorrichtung zum Herstellen einer Elektrolyt-Leitsonde
US761352*A US3489544A (en) 1965-10-22 1968-02-19 Apparatus for making an electrolyte guide member
US766005*A US3556758A (en) 1965-10-22 1968-02-19 Method for making an electrolyte guide member
BE712508D BE712508A (de) 1965-10-22 1968-03-20

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US501643A US3384567A (en) 1965-10-22 1965-10-22 Electrolyte guide member
US76135268A 1968-02-19 1968-02-19
US76600568A 1968-02-19 1968-02-19

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US3384567A true US3384567A (en) 1968-05-21

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US501643A Expired - Lifetime US3384567A (en) 1965-10-22 1965-10-22 Electrolyte guide member
US761352*A Expired - Lifetime US3489544A (en) 1965-10-22 1968-02-19 Apparatus for making an electrolyte guide member
US766005*A Expired - Lifetime US3556758A (en) 1965-10-22 1968-02-19 Method for making an electrolyte guide member

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US761352*A Expired - Lifetime US3489544A (en) 1965-10-22 1968-02-19 Apparatus for making an electrolyte guide member
US766005*A Expired - Lifetime US3556758A (en) 1965-10-22 1968-02-19 Method for making an electrolyte guide member

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US (3) US3384567A (de)
BE (1) BE712508A (de)
CH (1) CH475363A (de)
DE (1) DE1565553C3 (de)
GB (1) GB1147952A (de)
NL (1) NL150406B (de)
SE (1) SE333438B (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522699A (en) * 1981-06-29 1985-06-11 Statni Vyzkumny Ustav Ochrany Materialu G.V. Indicator terminal for coulometric measuring devices
US4769118A (en) * 1985-12-13 1988-09-06 Ae Plc Process for the curvilinear formation of holes

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1159357B (it) * 1983-02-08 1987-02-25 Olivetti & Co Spa Procedimento ed apparecchiature per la fabbricazione di elementi profilati di materiale deformabile particolarmente per dispositivi stampanti a getto di inchiostro
US4530712A (en) * 1984-03-26 1985-07-23 Kopf J David Pipette puller
US4578101A (en) * 1984-09-26 1986-03-25 At&T Technologies, Inc. Method for stretching a glass rod
US4631079A (en) * 1984-09-26 1986-12-23 At&T Technologies, Inc. Method for stretching a glass rod
US4820321A (en) * 1987-08-13 1989-04-11 American Telephone And Telegraph Company Method and apparatus for fabricating an expanded beam cylindrically terminated optical fiber taper
DE3913875C1 (de) * 1989-04-27 1990-08-09 Heraeus Quarzschmelze Gmbh, 6450 Hanau, De
CA2121704A1 (en) * 1993-06-21 1994-12-22 Paul Andrew Chludzinski Apparatus and method for making an optical fiber preform
FR2774372B1 (fr) * 1998-02-05 2000-03-03 Alsthom Cge Alcatel Procede de fibrage en continu de preformes pour la fabrication de fibres optiques
JP3642993B2 (ja) * 1999-10-28 2005-04-27 株式会社小糸製作所 アークチューブの製造方法
CN106541192A (zh) * 2017-01-19 2017-03-29 常州工学院 一种六角形孔电解加工装置

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1416929A (en) * 1921-11-07 1922-05-23 William E Bailey Art of electrolysis
US2937124A (en) * 1955-06-23 1960-05-17 Philco Corp Method of fabricating semiconductive devices and the like

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3114621A (en) * 1957-04-09 1963-12-17 Kiraly Tibor Apparatus for cutting off lengths of glass tubing
US3091105A (en) * 1959-10-12 1963-05-28 Morrill Vaughan Apparatus for shrinking tubular glass blank

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1416929A (en) * 1921-11-07 1922-05-23 William E Bailey Art of electrolysis
US2937124A (en) * 1955-06-23 1960-05-17 Philco Corp Method of fabricating semiconductive devices and the like

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522699A (en) * 1981-06-29 1985-06-11 Statni Vyzkumny Ustav Ochrany Materialu G.V. Indicator terminal for coulometric measuring devices
US4769118A (en) * 1985-12-13 1988-09-06 Ae Plc Process for the curvilinear formation of holes

Also Published As

Publication number Publication date
GB1147952A (en) 1969-04-10
BE712508A (de) 1968-07-31
SE333438B (de) 1971-03-15
NL150406B (nl) 1976-08-16
NL6608162A (de) 1967-04-24
CH475363A (de) 1969-07-15
DE1565553C3 (de) 1974-01-10
DE1565553A1 (de) 1970-02-05
US3489544A (en) 1970-01-13
US3556758A (en) 1971-01-19
DE1565553B2 (de) 1973-06-07

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