US3360972A - Magnetomotive metal working device - Google Patents

Magnetomotive metal working device Download PDF

Info

Publication number
US3360972A
US3360972A US453225A US45322565A US3360972A US 3360972 A US3360972 A US 3360972A US 453225 A US453225 A US 453225A US 45322565 A US45322565 A US 45322565A US 3360972 A US3360972 A US 3360972A
Authority
US
United States
Prior art keywords
coil
hammer
contact
workpiece
bolt
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
US453225A
Other languages
English (en)
Inventor
Robert J Schwinghamer
Leslie E Foster
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.)
National Aeronautics and Space Administration NASA
Original Assignee
Nasa Usa
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 Nasa Usa filed Critical Nasa Usa
Priority to US453225A priority Critical patent/US3360972A/en
Priority to BE680337D priority patent/BE680337A/xx
Priority to GB19223/66A priority patent/GB1146055A/en
Priority to FR59912A priority patent/FR1478170A/fr
Priority to DE19661552040 priority patent/DE1552040C/de
Priority to NL6605900A priority patent/NL6605900A/xx
Priority to SE5933/66A priority patent/SE303079B/xx
Application granted granted Critical
Publication of US3360972A publication Critical patent/US3360972A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/20—Electromagnets; Actuators including electromagnets without armatures
    • H01F7/202—Electromagnets for high magnetic field strength
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/14—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces applying magnetic forces

Definitions

  • ABSTRACT OF THE DISCLOSURE A magnetomotive metal Working portable hammer unit having a reinforced flat spiral coil at one end electrically connected to a pair of abutting metallic electrical contact plates with an insulation block separating the coil and the contact plates.
  • the coil, insulation block and contact plates are housed in a shell of insulating material.
  • the various components of the hammer are clamped together by an axial bolt extending from the center of the coil to the opposite end of the hammer. Relatively long transmission lines connect the hammer to a power supply and electrical energy within the hammer passes through the contact blocks, coil and axial bolt.
  • the present invention relates generally to the field of metal working and particularly to a device for manipulating metallic material by the use of an intense transient magnetic field.
  • Portable magnetomotive devices previously proposed suffer from a number of serious drawbacks.
  • the magnetic coils incorporated in these devices have deteriorated quite rapidly, even after relatively few applications.
  • the quantity of energy delivered by previous devices was deficient, variable and unpredictable from one discharge to the next.
  • Electrical arcing from the metal housing of these devices to the workpiece was often intolerable because of the attendant danger and marring of the workpiece.
  • a further object of the invention is to provide a magnetomotive 'hammer incorporating a unique structural system which imparts the necessary rigidity to the electromagnetic coil of the hammer and assures a constant and positive electrical contact between the coil and the transmission lines extending between the hammer and its power source.
  • Another object of the invention is to provide a magnetomotive hammer which repeatedly delivers an adequate and precisely predictable amount of energy useful and controllable for metal working operations.
  • the invention comprises a portable, compact, and lightweight hammer unit which is connected to an electric power supply through relatively long transmission lines.
  • the hammer unit includes a multi-turn coil mounted at one end of a housing shell.
  • the turns of the coil are separated by insulating material and the entire coil is strengthened by incorporating therein a medium for interlocking the turns.
  • Electrical contact from the center turn of the coil is through a heavy bolt extending axially through the hammer from the coil center.
  • Electrical contact from the outer turn of the coil is through a metallic element connected to the outer turn of the coil at one end and to a metallic contact block at the other end.
  • the space between the coil and the contact block, not occupied by the axial bolt, is filled with an insulating material such as Teflon.
  • Bearing upon the first contact block is a second contact element which is connected to one conductor of each of the transmission lines going to the power supply.
  • the second conductor of each of the transmission lines is connected, as by connecting studs, to a metallic plate which constitutes the top element of the hammer unit, with an insulating material separating this top plate from the second contact element. All of the elements of the hammer unit are firmly clamped together by the axial bolt which receives a nut at its upper end that bears on the top plate. This structural system insures a rigid coil and a constant and positive electrical contact from the coil to the transmission lines.
  • the hammer unit is encased in a shell of insulating material.
  • the hammer unit is equipped with a device for clamping the hammer unit to the workpiece thereby eliminating the necessity of manually holding the hammer against the workiece.
  • FIGURE 1 is a schematic perspective view of a magnetomotive metal working device including a diagram of a circuit for supplying and controlling electrical energ for the metal working device.
  • FIGURE 2 is a cross sectional view of the metal working device of FIGURE 1.
  • FIGURE 3 is a cross sectional view taken along line 33 of FIGURE 2.
  • FIGURE 4 is a perspective view of the metal working device equipped with an apparatus for clamping it to a workpiece.
  • FIGURE 1 therein is shown a magnetomotive metal working hammer unit 11, a principal component of which is a fiat spiral coil 13 (FIGURE 2).
  • a system is provided for supplying and controlling pulses of electrical energy so as to produce a varying magnetic field of high intensity about the coil.
  • This system includes a high-voltage source 15 for charging a capacitor bank 17. Connected in series with the voltage source 15 are switch 19 and a current limiting resistor 21.
  • a switching means 23, such as an ignitron, is connected in series with the capacitor bank.
  • the electrical energy system is connected to the hammer 11 by a plurality of transmission lines 25, preferably coaxial cables, which enter the electrical energy system through a connector box 27.
  • the transmission lines be quite long, extending about feet in one embodiment, so that the hammer unit, which is very light and easily carried, may be taken a substantial distance from the power supply to the location of the workpiece.
  • the electrical impulse it is desirable for the electrical impulse to be delivered over a relatively longer period of time, when long transmission lines are used.
  • coaxial cables may be used in which the inner conductor comprises a metallic sheath surrounding a polyethylene insulating core, and the outer conductor comprises a metallic sheath surrounding a polyethylene insulator separating the two conducting elements.
  • the hammer unit 11 comprises two distinct subunits designated as a coil assembly 31 and a shell assembly 33, the latter being mounted atop the former.
  • the coil assembly 31 includes the coil 13 which is wound from a fairly thin and narrow strip of electrical conducting material such as beryllium copper.
  • the coil constituted approximately 14 turns wound from a x 1 /2" x 210" strip of Berylco 25.
  • T 0 assure electrical insulation between the turns of the coil, a strip of special insulating material 35 such as Mylar is interposed between the coil turns.
  • the coil In the design of the coil 13, somewhat conflicting requirements are evidenced. First, it is essential that the coil be structurally rigid to withstand the intense magnetic pressures exerted between it and the workpiece. It is apparent that these pressures tend to cause a displacement of shucking out of the coil turns from their coplanar positions. Therefore, from the standpoint of giving rigidity to the coil and of minimizing the resistance of the coil winding, the use of a coil conductor of relatively large cross sectional dimensions would be indicated. However, it is beneficial in some respects to use a coil conductor of rather narrow and thin cross section in order to give the finished coil a compact diameter and thickness while at the same time permitting a sufficient number of coil turns to produce an adequate magnetic field density.
  • a relatively thin and narrow conductor is used but with a strengthening system comprising high-strength, nonconductive rods 37 extending radially at intervals from the center of the coil, these rods being disposed in passageways 39 passing through the coil turns to thereby interlock the coil turns and prevent any of them from shucking out.
  • the coil conductor can have milled slots which, while equally spaced, occur at random in the finished coil.
  • the potting material fills these slots during vacuum potting, thereby providing a strong conductor retaining force.
  • the other alternative provides for retaining force by virtue of polyurethane potting material which covers the conductors and the Mylar insulating material on the face of the coil. The Mylar is deliberately left slightly short to facilitate the forming of the polyurethane end plate so-to-speak.
  • the coil 13 is housed within a cylindrical electrically conducting element 41 with the bottom surface of the coil positioned substantially flush with the lower end of the element 41.
  • An electrical connection 43 is made, as by brazing, between the outer turn of the coil 13 and the inner surface of the conducting element 41.
  • the rods 37 extend through holes 45 of the element 41 and terminate flush with the outer surface thereof.
  • a relatively large bolt 47 which extends axially through the hammer 11 and has a threaded upper end 49.
  • the bolt 47 has a lower portion 51 of a diameter approximately the same as the inside diameter of the inner turn of the coil 13 into which the portion 51 is in serted and connected at 53 as by brazing.
  • the diameter of the bolt 47 changes, forming a shoulder 55.
  • a retaining ring 57 encircles the bolt 47 and bears on the shoulder 55. This ring prevents pulling in of the coil center conductors.
  • the bolt 47 is embedded in a block of insulating material 59, such as Teflon.
  • This insulating block bears on the upper surface of the coil 13 and substantially fills the cylindrical element 41 and includes a portion 61 of reduced diameter which rises above the assembly.
  • the contact block 65 has a concentrically disposed buttress 67, and a central hole 69 through which the portion 61 of the insulating block 59 passes.
  • an insulating shell 71 For completing the housing of the hammer, an insulating shell 71, with Teflon again being a very suitable material, covers the entire external surface of the cylindrical element 41. This is extremely important, and prevents arcing to the workpiece due to induced voltages.
  • the shell 71 and the cylindrical element 41 are threadedly joined at 73. At its upper end the shell 71 has a laterally projecting circumferential flange 75.
  • a stainless steel clamp band 77 provided with a clamp bolt 79 is applied around the shell 71 opposite the coil 13. Induction losses are fare less in stainless steel than in good electrical conductors.
  • the coil potting process is preferably performed after the other components of the coil assembly 31 have been assembled so that the potting 81 will also flow into engagement with adjacent surfaces of the bolt 47, insulating block 59, cylindrical element 41 and the shell 71. This causes the coil to be bonded to the adjacent elements and therefore more integrated and firmly set in the assembly.
  • a good material for potting the coil is one produced by Product Research Corporation under the designation PRC 1538 with Metal Primer PR1531.
  • the potting 81 serves as an excellent insulator and also has a reasonably high tensile and shear strength thus increasing the overall rigidity of the coil.
  • the shell assembly 33 is mounted on the coil assembly 31 and comprises an insulating block 83 having a recess 85 therein which receives a hot contact plate 87. Connection between insulating block 83 and the conductor plate 87 is through screw 89.
  • the periphery of the insulating block 83 coincides with the periphery of the flange 75 and connecting screws 91 extend through the flange 75 into the insulating block 83.
  • the hot contact plate 87 is coextensive with the contact block 65 and is provided with a circular groove 93 which mates with the buttress 67 of the contact block. Aligned holes 95 and 97 in the contact plate 87 and the insulating block 83, respectively, are occupied by the portion 61 of the insulating block 59.
  • each of the connecting studs 103 is axially aligned with a passage 106 through the insulating block 83 and with an aperture 107 in the contact plate 87 thus permitting an inner conductor 109 of each coaxial cable 25 to extend to and be clamped by a set screw 111 in the contact plate 87.
  • the axial bolt 47 passes through a hole 113 in the center of the ground plate 101 and receives a nut 115 which bears on the ground plate 101.
  • the necessary torque is applied to the nut 115 to bind and pull together the coil assembly 31 and the shell assembly 33. All of the components of the hammer are thus firmly bound and circuit within the hammer unit 11 is through conductors 109, contact plate 87, contact block 65, cylindrical element 41, coil 13, bolt 47, nut 115, ground plate 101, studs 103 and sleeves 105.
  • the ground plate 101, contact plate 87, contact block 65 and the cylindrical element 41 are preferably made of a soft metal such as brass.
  • the unique structural arrangement of the hammer described above imparts the necessary rigidity to the hammer and its coil to give durability to the device. Moreover, the quantity of the metal working energy delivered by the hammer is adequate, controllable, repeatable and predictable due to the above described means of providing constant and positive electrical contact and conduction within the hammer.
  • the resulting structure is entirely inadequate with regard to burst strength at high energy levels.
  • arcing from the housing to the workpiece is eliminated by the provision of an insulating exterior for the hammer.
  • the hammer may be equipped with a quick release clamping device 119 for holding the hammer unit to a workpiece 121, thereby eliminating the necessity of manually holding the hammer against the workpiece.
  • the clamping device includes a frame 123 having an'opening 125 therein encircling the hammer and being releasably secured to the hammer by set screws 127
  • At opposite ends of the, frame 123 are dovetail grooves 129 in which are releasably fixed by set screws 131 guides 133.
  • cylinders 135 each containing a piston (not shown) which may be operated, pneumatically, for example, with air pressure being supplied through tubes 137 and 139.
  • the piston actuates a clamping bar 141 through a rod 143.
  • the clamping bar 141 engages and slides along the guides 133 through slots 145.
  • the clamp device 119 may be used to position the hammer unit 11 between projections, such as stiifening tees 147 of the workpiece 121.
  • Components of the clamp device are easily removable from the frame 123 which may be more or less normally secured to the hammer 11 and used to facilitate handling of the hammer during operation when the clamp device is not used.
  • a magnetomotive metal Working device comprising:
  • said clamping means comprising a bolt extending axially of said hammer unit and having one end thereof connected to said coil;
  • the device of claim 1 including means for strengthening said coil, said strengthening means including means passing transversely through said turns to interlock said turns in said coplanar relation.
  • said hammer unit comprises an exterior insulating shell in the region of said coil conductor.
  • the device of claim 1 including quick release means for holding said hammer unit to a workpiece.
  • a portable hammer unit for electromagnetic metal working comprising:
  • a portable hammer for electromagnetic metal working comprising:
  • said means including a pair of metallic contact elements within said housing with each of said elements having a contact surface abutting a contact surface of the other element;
  • said clamping means extending through said contact elements comprising a bolt extending axially of said housing and having one end thereof connected to said coil.
  • a portable hammer as defined in claim 10 including means releasably secured to said hammer for releasably holding said hammer to a workpiece.
  • a portable hammer for magnetomotive metal working comprising:
  • insulating means contained within said housing element and extending between said coil and said contact block;
  • An electromagnetic metal working device comprising:
  • a conducting coil having a plurality of coplanar spiral turns with insulating means disposed between said turns;
  • said contact block and said contact plate having aligned central holes therethrough through which passes said bolt;
  • (13) means including said bolt for clamping said coil, insulating material, contact block and contact plate together to form a rigid unit;
  • the device as defined in claim 16 including means comprising a potting material for binding together the turns of said coil and for binding said coil to said tubular conducting element and said insulating shell.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Electromagnets (AREA)
  • General Induction Heating (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Jigs For Machine Tools (AREA)
US453225A 1965-05-04 1965-05-04 Magnetomotive metal working device Expired - Lifetime US3360972A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US453225A US3360972A (en) 1965-05-04 1965-05-04 Magnetomotive metal working device
BE680337D BE680337A (US20100012521A1-20100121-C00001.png) 1965-05-04 1966-04-29
GB19223/66A GB1146055A (en) 1965-05-04 1966-05-02 Improvements relating to magnetomotive metal working devices
FR59912A FR1478170A (fr) 1965-05-04 1966-05-02 Dispositif de traitement des métaux
DE19661552040 DE1552040C (de) 1965-05-04 1966-05-02 Tragbare magnetische Metallbearbeitungsvorrichtung
NL6605900A NL6605900A (US20100012521A1-20100121-C00001.png) 1965-05-04 1966-05-02
SE5933/66A SE303079B (US20100012521A1-20100121-C00001.png) 1965-05-04 1966-05-02

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US453225A US3360972A (en) 1965-05-04 1965-05-04 Magnetomotive metal working device

Publications (1)

Publication Number Publication Date
US3360972A true US3360972A (en) 1968-01-02

Family

ID=23799679

Family Applications (1)

Application Number Title Priority Date Filing Date
US453225A Expired - Lifetime US3360972A (en) 1965-05-04 1965-05-04 Magnetomotive metal working device

Country Status (6)

Country Link
US (1) US3360972A (US20100012521A1-20100121-C00001.png)
BE (1) BE680337A (US20100012521A1-20100121-C00001.png)
FR (1) FR1478170A (US20100012521A1-20100121-C00001.png)
GB (1) GB1146055A (US20100012521A1-20100121-C00001.png)
NL (1) NL6605900A (US20100012521A1-20100121-C00001.png)
SE (1) SE303079B (US20100012521A1-20100121-C00001.png)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3581541A (en) * 1969-04-01 1971-06-01 Gulf Energy & Environ Systems Method and apparatus for magnetic forming
US3599462A (en) * 1968-11-25 1971-08-17 Gulf Oil Corp Ceramic core electromagnetic forming coil
US3631698A (en) * 1969-12-29 1972-01-04 Aeg Elotherm Gmbh Method and apparatus for hot straightening elongated metal workpieces
US3747382A (en) * 1967-10-19 1973-07-24 Univ Ohio State Metal working apparatus and process
US5231747A (en) * 1990-12-21 1993-08-03 The Boeing Company Drill/rivet device
US5263236A (en) * 1990-12-21 1993-11-23 The Boeing Company Drill quill bearing assembly
US5983478A (en) * 1996-09-18 1999-11-16 The Boeing Company Tube forming on an end fitting

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2035179B (en) * 1978-11-23 1982-09-02 G Sojuz Z Mek Ochistke Kotloag Method and device for reinforcing metalitem

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2976907A (en) * 1958-08-28 1961-03-28 Gen Dynamics Corp Metal forming device and method
US3114585A (en) * 1962-02-06 1963-12-17 Gen Dynamics Corp Forming apparatus
US3115857A (en) * 1961-06-05 1963-12-31 Republic Aviat Corp Metal forming apparatus
US3195335A (en) * 1962-12-07 1965-07-20 Gen Dynamics Corp Coil construction

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2976907A (en) * 1958-08-28 1961-03-28 Gen Dynamics Corp Metal forming device and method
US3115857A (en) * 1961-06-05 1963-12-31 Republic Aviat Corp Metal forming apparatus
US3114585A (en) * 1962-02-06 1963-12-17 Gen Dynamics Corp Forming apparatus
US3195335A (en) * 1962-12-07 1965-07-20 Gen Dynamics Corp Coil construction

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3747382A (en) * 1967-10-19 1973-07-24 Univ Ohio State Metal working apparatus and process
US3599462A (en) * 1968-11-25 1971-08-17 Gulf Oil Corp Ceramic core electromagnetic forming coil
US3581541A (en) * 1969-04-01 1971-06-01 Gulf Energy & Environ Systems Method and apparatus for magnetic forming
US3631698A (en) * 1969-12-29 1972-01-04 Aeg Elotherm Gmbh Method and apparatus for hot straightening elongated metal workpieces
US5231747A (en) * 1990-12-21 1993-08-03 The Boeing Company Drill/rivet device
US5263236A (en) * 1990-12-21 1993-11-23 The Boeing Company Drill quill bearing assembly
US5404633A (en) * 1990-12-21 1995-04-11 The Boeing Company Method of dynamically supporting a drill quill in a drill/rivet machine
US5577315A (en) * 1990-12-21 1996-11-26 The Boeing Company Method of upsetting rivets
US5621963A (en) * 1990-12-21 1997-04-22 The Boeing Company Differential capacitance in an electromagnetic riveter
US5685058A (en) * 1990-12-21 1997-11-11 The Boeing Company Method for direct insertion of a headed rivet into a countersunk hole
US5752306A (en) * 1990-12-21 1998-05-19 The Boeing Company Method for upsetting a headed rivet by differential initiation of opposed electromagnetic rivet drivers
US5983478A (en) * 1996-09-18 1999-11-16 The Boeing Company Tube forming on an end fitting

Also Published As

Publication number Publication date
FR1478170A (fr) 1967-04-21
SE303079B (US20100012521A1-20100121-C00001.png) 1968-08-12
DE1552040A1 (de) 1969-04-10
BE680337A (US20100012521A1-20100121-C00001.png) 1966-10-31
DE1552040B2 (de) 1972-12-14
NL6605900A (US20100012521A1-20100121-C00001.png) 1966-11-07
GB1146055A (en) 1969-03-19

Similar Documents

Publication Publication Date Title
RU2178349C2 (ru) Соединение или сварка металлических объектов посредством электромагнитного поля
US3372566A (en) Device for forming metallic workpieces by pulsed magnetic fields
US3214511A (en) Casing and insulator bushing assembly
US3115857A (en) Metal forming apparatus
US3252313A (en) Electromagnetic forming method and apparatus
US3108325A (en) Forming device
US3360972A (en) Magnetomotive metal working device
US4143532A (en) Inductor for forming metals by the pressure of a pulsed magnetic field
US3429159A (en) Forming apparatus
US3391558A (en) Device for magnetic-pulse forming of metallic workpieces
US3195335A (en) Coil construction
US4024370A (en) Toroidal resistance welding transformer
US3345844A (en) Coil for magnetic forming
US3203211A (en) Tubing fabrication
US3124726A (en) Howland
DE4423992C2 (de) Elektromagnetischer Generator für schnelle Strom- und Magnetfeld-Impulse und seine Verwendungen
Wilson et al. Design of efficient flux concentrators for pulsed high magnetic fields
US3852985A (en) Device for processing elongated tubular workpieces by pressure waves
DE1157320B (de) Verfahren zur Verminderung der bei der Metallumformung durch Magnetfelder erforderlichen Kraefte
US2218669A (en) Core of comminuted magnetic material
Foster et al. Magnetomotive metal working device Patent
US3555867A (en) Method and appratus for precision sizing and joining of large diameter tubes
US3438230A (en) Apparatus for electrodynamically forming solid bodies
US2455057A (en) Electric welding apparatus
US2416454A (en) Welding machine