US2348032A - Power mechanism for induction heating apparatus - Google Patents

Power mechanism for induction heating apparatus Download PDF

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Publication number
US2348032A
US2348032A US444345A US44434542A US2348032A US 2348032 A US2348032 A US 2348032A US 444345 A US444345 A US 444345A US 44434542 A US44434542 A US 44434542A US 2348032 A US2348032 A US 2348032A
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Prior art keywords
sleeve
transformer
annular
connections
primary
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US444345A
Inventor
Howard E Somes
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Budd Induction Heating Inc
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Budd Induction Heating Inc
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Priority claimed from US392867A external-priority patent/US2411698A/en
Application filed by Budd Induction Heating Inc filed Critical Budd Induction Heating Inc
Priority to US444345A priority Critical patent/US2348032A/en
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00Heating by electric, magnetic or electromagnetic fields
    • H05B6/02Induction heating
    • H05B6/10Induction heating apparatus, other than furnaces, for specific applications
    • H05B6/101Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces
    • H05B6/102Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces the metal pieces being rotated while induction heated
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00Heating by electric, magnetic or electromagnetic fields
    • H05B6/02Induction heating
    • H05B6/10Induction heating apparatus, other than furnaces, for specific applications
    • H05B6/101Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces

Definitions

  • the present invention relates to apparatus for heat treating by electromagnetic induction and by quenching the surfaces of tubular and cyiindrical articles, and particularly to the means for supplying high frequency energy to the inducing coil of the apparatus.
  • An object of this invention is to provide an electromagnetic induction Aheating apparatus in which the transformer has an .improved construction and arrangement for connecting the transformer secondary to the heating coil, and also Vfor connecting the transformer primary to the supply circuit.
  • Figure 1 is a perspective view of the apparatus looking toward its front and one of its sides and illustrating the general arrangement of parts;
  • Figure 2 is a vertical section taken through the upper portion of the machine to willustrate the transformer mechanism constructed in accordance with one embodiment of .this invention
  • Figure 3 is a top planview of the apparatus, a portion of the same being cut away to show the electrical connections;
  • Figure 4 is a horizontal section taken substan tially on the line 6-6 of Figure 2.;
  • Figure is a. rear view partly in section of the transformer.
  • a heat treat-v ing apparatus comprising a rigid uprightI frame 40 of hollow box-like section having a vvertical channel or recess 42 in the front face thereof which provides in effect spaced vertical columns 44 Vand 46 at either side of the forward face of the frame 40.
  • a pair of spaced upright parallel -rods 48 and 50 Secured to the columns and 46 is a pair of spaced upright parallel -rods 48 and 50 which are-secured to the frame 40 at the bottom through clamping members 52 and 54 and at the top through clamping members 5B and 50.
  • the rods 48 and l50 extend above the top clamping members 58 andV 58 and support a cross-tie or bridging member 60 upon which a switching transformer 62 and its motivating cylinder B4 are mounted and from which the electrical conductor arbor 66 extends.
  • the in- 5 ducing head, noi; shown, is supported from the end and electrically connected with the arbor -66 to receive electrical current therefrom.
  • a carriage 88 composed of sleeves 'l0 and 'I2 telescoped with the rods 48 and 50 and connectedl together by the lower chuck-supporting member 14, and upper chuck-supporting member 18 and a guiding bridge 'I8 is arranged to be reciprocated relative to the rods 48 and 50.
  • the workpiece 80 which is here shown as in the form l5 of a tubular cylindrical lobject is held in proper 2Q tively.
  • a bracket 82 which supports the quenching mechanism comprising ajreciprocable quench rod 84 having at its uppr end a nozzle, not shown.
  • the elevating and retracting apparatus for the quench rod 84 extends below the bracket 82 as indicated at 86.
  • the article or workpiece 80 is placed in position between the clamping chucks 11 and 19 and the upper chuck T1 is lowered to properly locate the article, then the quench rod y84 is raised through the workpiece 80 to position the quench head adjacent the heating head H in end-to-end relation as set forth in my copending application aforesaid.
  • the carriage 68 isV elevated so that the lower end of the article is adjacent the inducing head H and then the carriage is actuated to move downwardly to progressively move the workpiece relative to the heating and quenching heads during which .time the heating head is energized from the transformer mechanism to -be presently described and the quenching head is supplied with quenching fluid, all as fully described in my said application.
  • the cap bridgingY member and transformer support G0 is provided with a substantially annular barrel-shaped transformer casing 92 having cooling fins 94 thereon.
  • the lower annular ange 9B of the casing 92 is seated upon the rim 98 of an annular aperture
  • 'I'he annular flange 96 additionally supports on its underside an apertured plate
  • 04 is a transformer secondary supporting sleeve
  • 0 are secured together and in place upon the sleeve
  • 22 is provided exteriorly with an open channel
  • 2 is interrupted as indicated on the left by a blockl of insulation
  • 0 at the upper end and at the left as illustrated in Figure 4 is recessed to receive a shoulder
  • 42 is insulated from the sleeve
  • 42 having shoulders
  • 42 is fitted into a recess
  • 0 which in effect form the terminals, are provided with ports
  • 02 sleeved in insulating material extend tothe ports
  • 04 makes electrical connection with the sleeve
  • 40 is provided with a resilient sliding split sleeve connecting member
  • 14 is provided in the transformer
  • 'I'he primary consists of an annulus of radially arranged laminated magnetic material
  • 02 with its primary is slidable snugly' within the casing 02 from the position shown (see Figure 2) into the space indicated by the reference character
  • 10 may be shifted from a position adjacent the secondary winding to a position adjacent the annular body of magnetic material
  • 00 is secured to the sleeve
  • 00 is provided with an inspection window 2
  • the yoke is also provided with a clearance slot 2
  • 00 are effected through a block of insulating material 222 arranged in the annulus of magnetic material
  • Each of the connections 233 and 232 is provided with a ilange sleeve 242 anchored to the insulating block 224 by the cap screws 244 to prevent rotation.
  • Each of the sleeve portions is provided-with a lug 24B toV which is secured resiliently carried contact iingers 248 adapted to ride on spaced parallel contact bars 250 and 252 (see Figures 4 and 5).
  • the sleeve 242 has a portion thereof partially severed from the remainder as indicated at 254 (see Figure 4) and a lug 258 adapted to cooperate with the lug 245 for clamping the partially severed end of the sleeve tightly around the connections 230 and 232 extending through the sleeve.
  • and. 233 for supplying coolant to the hollow primary conductor areconnected to the outer ends of the tubular connections 230 and 232 which for the purpose of supplying coolant to the primary winding provldea continuous passage thereto.
  • of the partition 234 of the insulating block 224 form an insulating barrier between the exposed ends of the connections 230 and 232 and the adjacent spaced contact bars 250 and 252 so that ilashover or electrical breakdown between the connection 230 and-the bar 253 and the connection 232 and the bar 252 is assured against.
  • and 252 are mounted upon insulating blocks 252 and 280 the latter in turn being mounted upon lugs 25
  • the lower ends of the contact bars 250 and 252 are provided with coaxial clamping members 268 and 2l! (see Figure 5) adapted to securely connect with the concentric tubular conductors 210 and 212, vthe conductors being insulated from one another by an insulating sleeve 214 and insulated from the supporting members 213 and 21B through which they pass by a further insulating sleeve 280.
  • the concentric conductors 210 and 212 extend' into a pothead, not shown, where they are connected to power supply conductors.
  • the arbor 36 comprises the concentric conductors I and Ill depending from the transformer 62, thesame extending to the heat treat head to supply electrical energy thereto.
  • a frame a stationary annular support mounted on said frame, a sleeve secured to the inner edge of said support and extending upwardly therefrom, a transformer including a secondary supported on the upper end of said sleeve; a current conducting arbor comprising an outer arbor member mounted on the .lower end of said sleeve and extending downwardly therefrom. an inner arbor member insulated from said outer member and extending upwardly through said sleeve to a point adjacent said secondary, means electrically connecting said inner arbor member to one side of said secondi ary, and means electrically connecting the other vside of said secondary to said sleeve and through said sleeve to said outer arbor member.
  • a switching transformer comprising primary and secondary coils, rone of which is movable relatively to the other, a housing for said movable coil arranged to guide the Ymovement'. thereof 'and having a slot extending in the direction of' such movement,

Description

May 2, 1944.
H. E. soMEs 2,348,032
JEICIi 14,5. soMEs 2,348,032 POWER MECHANISM FOR INDUCTION HETING APPARATUS 'May 2, 1944.
original F11-ed May'io, v1941 #sheds-sneu 2 Hw v 244 im INVENTOR {40mm/ E. Somes'.
B'v v ATTORNEY POWER MEGHANISM FOR INDUCTION HEATING APPARATUS 'original Filed May 10, 1941 4 Smets-sheet s PIG 4 zal;
INVENTOR Houma la. som@Y`-I By' g y ATTORNEYl May 2, 1944. H. E. SMES 2,348,032
POWER MECHANISM FOR INDUCTION HEATING APPARATUS Original Filed May 10, 1941 4 Sheets-Sheet 4 25o 2151J o L /114 da. INVENTOR ze@ me Moword E Somes ATTORNEY Patented May 2, 19,44
rowEa MEcmANrsM Foa INDUCTION nEATrNG APPARATUS Howard E. Somes', Detroit, Mich., assignor to Budd Induction Heating, Inc., Philadelphia,
Pa., a corporation of Michigan Original application May 10, 1941, Serial No. 392,867. Divided and this application May 25, 1942, Serial No. 444,345
3 Claims.- (Cl. 171-1119) This application is a division of my copending application Serial No. 392,867, led May 10, i941, for Heat treating apparatus." l
The present invention relates to apparatus for heat treating by electromagnetic induction and by quenching the surfaces of tubular and cyiindrical articles, and particularly to the means for supplying high frequency energy to the inducing coil of the apparatus.
An object of this invention is to provide an electromagnetic induction Aheating apparatus in which the transformer has an .improved construction and arrangement for connecting the transformer secondary to the heating coil, and also Vfor connecting the transformer primary to the supply circuit.
With the above and other objects in view which "will be apparent from the following detailed description, the present invention consists in certain features of construction and combinations of parts to he hereinafter described with reference to the accompanying drawings, and then claimed.
In the drawings which illustrate a suitable embodiment of the invention:
Figure 1 is a perspective view of the apparatus looking toward its front and one of its sides and illustrating the general arrangement of parts;
Figure 2 is a vertical section taken through the upper portion of the machine to willustrate the transformer mechanism constructed in accordance with one embodiment of .this invention;
Figure 3 is a top planview of the apparatus, a portion of the same being cut away to show the electrical connections;
Figure 4 is a horizontal section taken substan tially on the line 6-6 of Figure 2.;
Figure is a. rear view partly in section of the transformer.
Referring to the accompanying drawings in which like numerals refer to like parts throughout the several views and particularly to Figure 1, there is generally illustrated a heat treat-v ing apparatus comprising a rigid uprightI frame 40 of hollow box-like section having a vvertical channel or recess 42 in the front face thereof which provides in effect spaced vertical columns 44 Vand 46 at either side of the forward face of the frame 40. Secured to the columns and 46 is a pair of spaced upright parallel - rods 48 and 50 which are-secured to the frame 40 at the bottom through clamping members 52 and 54 and at the top through clamping members 5B and 50. The rods 48 and l50 extend above the top clamping members 58 andV 58 and support a cross-tie or bridging member 60 upon which a switching transformer 62 and its motivating cylinder B4 are mounted and from which the electrical conductor arbor 66 extends. The in- 5 ducing head, noi; shown, is supported from the end and electrically connected with the arbor -66 to receive electrical current therefrom.
A carriage 88 composed of sleeves 'l0 and 'I2 telescoped with the rods 48 and 50 and connectedl together by the lower chuck-supporting member 14, and upper chuck-supporting member 18 and a guiding bridge 'I8 is arranged to be reciprocated relative to the rods 48 and 50. The workpiece 80 which is here shown as in the form l5 of a tubular cylindrical lobject is held in proper 2Q tively.
At the lower portion ofthe apparatus and between the clamping members 52 and 'i4` there is provided a bracket 82 which supports the quenching mechanism comprising ajreciprocable quench rod 84 having at its uppr end a nozzle, not shown. The elevating and retracting apparatus for the quench rod 84 extends below the bracket 82 as indicated at 86.
In the operation of the apparatus, the article or workpiece 80 is placed in position between the clamping chucks 11 and 19 and the upper chuck T1 is lowered to properly locate the article, then the quench rod y84 is raised through the workpiece 80 to position the quench head adjacent the heating head H in end-to-end relation as set forth in my copending application aforesaid. After this, the carriage 68 isV elevated so that the lower end of the article is adjacent the inducing head H and then the carriage is actuated to move downwardly to progressively move the workpiece relative to the heating and quenching heads during which .time the heating head is energized from the transformer mechanism to -be presently described and the quenching head is supplied with quenching fluid, all as fully described in my said application. The cap bridgingY member and transformer support G0 is provided with a substantially annular barrel-shaped transformer casing 92 having cooling fins 94 thereon. The lower annular ange 9B of the casing 92 is seated upon the rim 98 of an annular aperture |00 in the cap bridging member 60. 'I'he annular flange 96 additionally supports on its underside an apertured plate |02 forming,
u as will appear in Figure 4, together with a sleeve der ||0 arranged on the outside of the upper end of the sleeve |04 which ridge and shoulder engage complementary notches inthe ends of the y magnetic laminations.
`Arranged concentrically above the sleeve |04 is a transformer secondary supporting sleeve ||0, which cooperating with a detachable end flange member |20, is adapted to clamp a body of radially arranged laminations of magnetic material |22, the annular ridge |24' of the flange |20 and the annular dovetail shoulder |20 at the lower exterior end of sleeve |0 cooperating with complementary notches' in the laminations to secure the same together. The flange |20 and sleeve ||0 are secured together and in place upon the sleeve |04 bythe elongated bolts |20 extending through the sleeve wall and parallel to the axis thereof.
The body of laminated magnetic material |22 is provided exteriorly with an open channel |00 in which is arranged a secondary winding of the transformer, the secondary winding as'show'n being constituted by three turns of four hollow rectangular cross-section conductors |02 in parallel, the terminals of `which will appear on the left-hand side oi Figure 2. In ordereto provide terminal connections to the secondary winding |32, the annular body of magnetic material ||2 is interrupted as indicated on the left by a blockl of insulation |34 through which the lower terminal connections |00 radially extend. The sleeve ||0 at the upper end and at the left as illustrated in Figure 4 is recessed to receive a shoulder |20 on the block |04 as well as a radial lug portion |40 of the annular terminal connecting sleeve |42, the lug being connected to the upper terminals |44 of the secondary winding. The connecting sleeve |42 is insulated from the sleeve ||0 through the oiset tubular insulating sleeve |45, the sleeve ||0 and the sleeve |42 having shoulders |40 and |40 adapted to be engaged by the offset of the insulating sleeve |45 and to be held in engagement and position by an annular nut |00 threaded in the end flange |20, and bearing upon a ring of insulating material |52 located on the end of the connectingsleeve |42. The lug |40 of the connecting sleeve |42 is fitted into a recess |54 formed in the insulating block |34. To provide for water cooling of the secondary conductors the radial lug |40 and the sleeve ||0, which in effect form the terminals, are provided with ports |50 and |50, which ports are connected to the hollow passageways through the conductors |02. Connections |00 and |02 sleeved in insulating material extend tothe ports |00 and |00, the connection |00 and its insulation passing through the lug |40 and both connections |00 and |02 and their insulation passing through Athe end flange |20.
It will be observed that the sleeve ||0 through the sleeve |04 makes electrical connection with the sleeve |00 forming the exterior tubular conductor of the arbor 00, while the sleeve |42 having the-connecting lug |40 is provided with a resilient sliding split sleeve connecting member |04, the same being threaded within the sleeve |42 and slidably engaging the end of a central concentric conductor |00 extending through the arbor and within a concentric layer of insulation |00. Since the conductors |00 and |00'are fixed relative to one another ata central point, such without the use of make and break contacts, a
vertically slidable primary |14 is provided in the transformer ||0. 'I'he primary consists of an annulus of radially arranged laminated magnetic material |10 secured in position between spaced opposed annular ridges |10 and |00 engaging complementary notches in the ends of the laminations, the ridges being located upon the inside of the shouldered end of a primary annular surrounding sleeve |02 and an end outer flange forming member |04, the end ange member and the sleeve being secured together by longitudinally extending elongated bolts |00.
The sleeve |02 with its primary is slidable snugly' within the casing 02 from the position shown (see Figure 2) into the space indicated by the reference character |00 so that the tubular primary winding |90 arranged in an open channel |02 within the annular body iof magnetic material |10 may be shifted from a position adjacent the secondary winding to a position adjacent the annular body of magnetic material ||2, which acts to, complete the magnetic circuit with the primary body of magnetic material |10 when the primary is moved into the space |00 and out of coupling with the secondary |02 and its magf netic material |22.
In order to move the sleeve |02 and the transformer primary, a substantially annular operating yoke |00 is secured to the sleeve |02 by the bolts |00 and is in turn secured to a piston rodv |00 of the transformer motivating cylinder 04, the rod being secured to the yoke by means of a split ring 200 secured in a groove 202 in the end of the rod and between interengaging annular threaded members 204 and 200 in the apertured boss 200 at the upper end of the yoke |90. The yoke |00 is provided with an inspection window 2|0 on its forward side adapted to align with the inspection window 2|2 of the vupper easing member 2|4. The yoke is also provided with a clearance slot 2|0 in the rear through which extend cooling conduits 2|0 and 220 to the secondary cooling connections |00 and |02, the conduit 220 being formed of. insulating tubular material so as to avoid short-circuiting the ungrounded terminal of the secondary winding |02.
Terminal connections to the primary winding |00 are effected through a block of insulating material 222 arranged in the annulus of magnetic material |10, the block being clamped in position in the same manner as the magnetic ma vided with a dividing partition 234 (see Figure the central portion 234 of which is` inclined to connect with the oilset or .staggered end portions l233 and 240, the partition thereby providing for insulation between the projecting ends of the connections 230 and 232. Each of the connections 233 and 232 is provided with a ilange sleeve 242 anchored to the insulating block 224 by the cap screws 244 to prevent rotation. Each of the sleeve portions is provided-with a lug 24B toV which is secured resiliently carried contact iingers 248 adapted to ride on spaced parallel contact bars 250 and 252 (see Figures 4 and 5). The sleeve 242 has a portion thereof partially severed from the remainder as indicated at 254 (see Figure 4) and a lug 258 adapted to cooperate with the lug 245 for clamping the partially severed end of the sleeve tightly around the connections 230 and 232 extending through the sleeve. Flexible hose connections 23| and. 233 for supplying coolant to the hollow primary conductor areconnected to the outer ends of the tubular connections 230 and 232 which for the purpose of supplying coolant to the primary winding provldea continuous passage thereto.
It will appear that thek end portions 238 and 24| of the partition 234 of the insulating block 224 form an insulating barrier between the exposed ends of the connections 230 and 232 and the adjacent spaced contact bars 250 and 252 so that ilashover or electrical breakdown between the connection 230 and-the bar 253 and the connection 232 and the bar 252 is assured against. As illustrated in Figures 4 and5 the contact bars 25| and 252 are mounted upon insulating blocks 252 and 280 the latter in turn being mounted upon lugs 25| on the inside of the relativelytangential extending portions 262 and. 28.4 of the transformer casing 32.
The lower ends of the contact bars 250 and 252 are provided with coaxial clamping members 268 and 2l! (see Figure 5) adapted to securely connect with the concentric tubular conductors 210 and 212, vthe conductors being insulated from one another by an insulating sleeve 214 and insulated from the supporting members 213 and 21B through which they pass by a further insulating sleeve 280. The concentric conductors 210 and 212 extend' into a pothead, not shown, where they are connected to power supply conductors.
As has previously been described the arbor 36 comprises the concentric conductors I and Ill depending from the transformer 62, thesame extending to the heat treat head to supply electrical energy thereto.
Although only one embodiment or modification of the invention has been illustrated and described, it is to be understood that the invention -is not limited tothe single embodiment but may be embodied in various mechanical andelectricai forms. As such changes in construction and arrangement of parts may be made without` departing from the spirit of the invention as will be apparent to those skilled in the art, reference will be had to the appended claims for a definition of the limits of the invention.
What is claimed is:
1. In a heat treating apparatus, a frame, a stationary annular support mounted on said frame, a sleeve secured to the inner edge of said support and extending upwardly therefrom, a transformer including a secondary supported on the upper end of said sleeve; a current conducting arbor comprising an outer arbor member mounted on the .lower end of said sleeve and extending downwardly therefrom. an inner arbor member insulated from said outer member and extending upwardly through said sleeve to a point adjacent said secondary, means electrically connecting said inner arbor member to one side of said secondi ary, and means electrically connecting the other vside of said secondary to said sleeve and through said sleeve to said outer arbor member.
2. In a heat treating apparatus, a switching transformer comprising primary and secondary coils, rone of which is movable relatively to the other, a housing for said movable coil arranged to guide the Ymovement'. thereof 'and having a slot extending in the direction of' such movement,
spaced contact bars adjacent and parallel to said slot, terminals movable,- with said coil and extending through said slot, and contact members connected to said terminals and slidably engaging saidI contact bars.
3. In a heat treating apparatus, a switching HOWARD E. BOMES.
US444345A 1941-05-10 1942-05-25 Power mechanism for induction heating apparatus Expired - Lifetime US2348032A (en)

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Application Number Priority Date Filing Date Title
US392867A US2411698A (en) 1941-05-10 1941-05-10 Induction heat-treating apparatus
US444345A US2348032A (en) 1941-05-10 1942-05-25 Power mechanism for induction heating apparatus

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2819431A (en) * 1952-12-05 1958-01-07 Louis R Maxwell Electromagnet
US2851582A (en) * 1954-07-21 1958-09-09 Western Electric Co Apparatus for brazing parts together

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2819431A (en) * 1952-12-05 1958-01-07 Louis R Maxwell Electromagnet
US2851582A (en) * 1954-07-21 1958-09-09 Western Electric Co Apparatus for brazing parts together

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