Inductor for inductively heating crank shafts

• US 5,451,749 A
• Filed: 12/27/1993
• Issued: 09/19/1995
• Est. Priority Date: 12/27/1993
• Status: Expired due to Term

• Current Assignee: Ajax Tocco Magnethermic Corporation (Park-Ohio Holdings Corporation)
• Original Assignee: Tocco, Inc. (Park-Ohio Holdings Corporation)
• Inventors: West, William D., Dunn, Jerry R., Griebel, Arthur H.
• Primary Examiner(s): Leung, Philip H.
• Application Number:
  US08/173,886
• Time in Patent Office: 631 Days
• Field of Search: 219/639, 219/673, 219/677, 219/676, 219/672, 148/572, 148/573, 266/129
• US Class Current: 219/639
• CPC Class Codes: H05B 6/101 for local heating of metal pieces
• CPC Class Codes: H05B 6/362 with flat coil conductors
• CPC Class Codes: H05B 6/40 Establishing desired heat distribution, e.g. to heat particular parts of workpieces
• CPC Class Codes: H05B 6/42 Cooling of coils
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49078 Laminated

Abstract

An inductor for inductively heating bearing surfaces of a crankshaft is machined from a block of copper to provide parallel, closely spaced and integrally joined inductor block portions having machined coolant passages therein. The machined inductor is rigidly supported between juxtaposed side plates having portions of the inner surfaces thereof machined to provide recesses which receive the inductor and in which the inductor is clampingly engaged between the plates. Positioning fingers are supported by the side plates to accurately position the active face of the inductor relative to a bearing surface to be heated, and tubular leads extend upwardly between the side plates for connecting the inductor across a source of power. An inlet conduit for coolant extends laterally between the side plates, and the tubular leads provide outlets for coolant flow from the inductor.

Claims

1. An inductor for inductively heating a crankshaft bearing surface having an axis, said inductor including a one-piece inductor block having upper and lower ends, parallel axially spaced opposite sides transverse to said axis and slot means dividing said block into first and second inductor block portions, each having upper and lower ends, said slot means including a slot transverse to said axis between said upper ends of said first and second block portions, each said block portion at said upper end thereof having an axial width greater than the axial width of said transverse slot, insulating material in said slot, each said block portion including arcuate inductor leg means extending outwardly and downwardly from said lower end thereof, said slot means providing for said inductor block to have terminal ends at said upper end thereof for connection to a source of electrical power and for said block portions and arcuate inductor leg means to provide a series current path between said ends, and means including recess means in said opposite sides providing coolant passageway means in each said block portion and the corresponding inductor leg means.

2. An inductor according to claim 1, wherein said means providing coolant passageway means includes cover means overlying said recess means and secured to the corresponding one of said opposite sides.

3. An inductor according to claim 1, wherein said slot means includes a slot dividing the upper end of one of said inductor block portions into first and second end portions providing said terminal ends.

4. An inductor according to claim 1, wherein said coolant passageway means includes inlet passageway means in said first block portion and outlet passageway means in said second block portion.

5. An inductor according to claim 4, wherein said slot means includes a slot dividing the upper end of said second block portion into first and second end portions providing said terminal ends, and said outlet passageway means includes an outlet end in each said first and second end portions.

6. An inductor according to claim 4, wherein said coolant passageway means further includes connecting passageway means in said bottom end of said inductor block connecting said inlet and outlet passageway means.

7. An inductor according to claim 6, wherein said inlet passageway means includes first and second inlet passages and said outlet passageway means includes first and second outlet passages, said slot means including a slot dividing the upper end of said second block portion into first and second end portions providing said terminal ends, and said first and second outlet passages having outlet ends respectively in said first and second end portions.

8. An inductor according to claim 7, wherein said first and second inlet passages have adjacent inlet ends in said first block portion.

9. An inductor according to claim 8, wherein said means providing coolant passageway means includes cover means overlying said recess means and secured to the corresponding one of said opposite sides.

10. An inductor for inductively heating a crankshaft bearing surface having an axis, said inductor including parallel axially adjacent first and second yoke portions including means for connecting said inductor to a source of electrical power, each said yoke portion having an upper end transverse to said axis and first and second yoke legs extending downwardly from said upper end and having lower ends laterally spaced apart relative to said axis, first and second arcuate inductor legs respectively integral with and extending laterally outwardly from the lower end of said first and second yoke legs of each said first and second yoke portions, said first inductor legs being connected at a location spaced from the lower ends of said first yoke legs, said second inductor legs being connected at a location spaced from the lower ends of said second yoke legs, each said first and second yoke portion and the corresponding first and second inductor legs having a surface transverse to said axis, and means including recess means in each said surface providing coolant passageway means in the upper end and in the first and second yoke legs and first and second inductor legs of each said first and second yoke portion.

11. An inductor according to claim 10, wherein said means providing coolant passageway means includes cover means overlying said recess means.

12. An inductor according to claim 10, wherein the upper end of one of said yoke portions includes first and second terminal end portions, said means for connecting said inductor to said source of power including said terminal end portion.

13. An inductor according to claim 10, and openings communicating said recess means in said first inductor legs and in said second inductor legs at said locations to connect said passageway means in said first and second yoke portions.

14. An inductor according to claim 13, wherein said passageway means includes inlet end means in one of said first and second yoke portions and outlet end means in the other.

15. An inductor according to claim 13, wherein said coolant passageway means in one of said first and second yoke portions includes first and second inlet passageway portions and said coolant passageway means in the other of said first and second yoke portions includes first and second outlet passageway portions respectively communicating with said first and second inlet portions through said openings.

16. An inductor according to claim 15, wherein said first and second inlet and first and second outlet passageway portions respectively include first and second inlet and first and second outlet recesses, and said means providing said coolant passageway means includes cover means overlying said recesses.

17. An inductor according to claim 16, wherein each said recess includes shoulder means inwardly of the corresponding surface, and said cover means includes a cover for each said recess engaging against the corresponding shoulder means and having an outer side generally coplanar with said corresponding surface.

18. An inductor according to claim 15, wherein the upper end of said other yoke portion includes first and second terminal end portions, said means for connecting said inductor to said source of power including said terminal end portions, said one yoke portion including an outer side edge transverse to said surface thereof, said first and second inlet passageway portions having inlet ends opening through said outer side edge of said one yoke portion, and said first and second outlet passageway portions having outlet ends opening respectively through said first and second terminal end portions of said other yoke portion.

19. An inductor according to claim 18, and coolant inlet tube means connected to said side edge of said one yoke portion for delivering coolant to said inlet ends of said first and second inlet passageway portions, said inlet tube means extending laterally outwardly from said side edge parallel to said surface of said one yoke portion.

20. An inductor according to claim 19, and first and second tubular conductors connected respectively to said first and second terminal end portions in flow communication with said outlet ends of said first and second outlet passageway portions, said first and second conductors extending upwardly from said other yoke portion parallel to said surface thereof.

21. An inductor according to claim 20, wherein said surface of said first and second yoke portions is an outer surface and said yoke portions have opposed planar inner surfaces parallel to the outer surfaces thereof, said first and second tubular conductors having opposed planar inner surfaces each coplanar with a different one of said inner surfaces of said yoke portions, and said opposed surfaces being spaced apart from about 0.020 to 0.040 inch.

22. An inductor according to claim 20, wherein said first and second tubular conductors have upper ends and said means for connecting said inductor to said source of power includes said first and second tubular conductors and first and second electrical coupling means respectively connected to said upper ends of said first and second conductors.

23. An inductor according to claim 22, wherein each said first and second coupling means includes coolant passageway means in flow communication respectively with the upper ends of said first and second tubular conductors.

24. An inductor according to claim 23, wherein said surface of said first and second yoke portions is an outer surface and said yoke portions have opposed planar inner surfaces parallel to the outer surfaces thereof, said first and second tubular conductors having opposed planar inner surfaces each coplanar with a different one of said inner surfaces of said yoke portions, and said opposed surfaces being spaced apart from about 0.020 to 0.040 inch.

25. An inductor according to claim 20, wherein said first and second inlet and first and second outlet passageway portions respectively include first and second inlet and first and second outlet recesses, and said means providing said coolant passageway means includes cover means overlying said recesses.

26. An inductor according to claim 25, wherein each said recess includes shoulder means inwardly of the corresponding surface, and said cover means includes a cover for each said recess engaging against the corresponding shoulder means and having an outer side generally coplanar with said corresponding surface.

27. An inductor according to claim 26, and flux concentrator means on said first and second inductor legs.

28. An inductor according to claim 10, and flux concentrator means on said first and second inductor legs.

29. An inductor assembly for inductively heating a crankshaft bearing surface having an axis, said inductor assembly comprising inductor means having top and bottom ends, said bottom end of said inductor means including arcuate inductor legs facing said bearing surface, said top end including means for connecting said inductor means to a source of electrical power, and support means for said inductor means, said support means including metal plate members having outer surfaces transverse to said axis and having axially opposed inner surfaces including first and second inner surface portions, said first inner surface portions being in facial engagement with one another and said second inner surface portions including means providing recess means for receiving said inductor means, and said support means further including support member means of insulating material in said recess means for clampingly engaging said inductor means between said plate members in spaced relationship to said recess means.

30. An inductor assembly according to claim 29, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, and said arcuate inductor legs being radially inwardly adjacent said peripheral edges.

31. An inductor assembly according to claim 30, wherein said inductor means includes lug means extending laterally outwardly from said inductor legs, said recess means includes lug receiving recess means extending between said plate members from said peripheral edges, and said support member means includes lug clamping member means.

32. An inductor assembly according to claim 31, and further including means fastening said lug clamping member means to said plate members and to said lug means.

33. An inductor assembly according to claim 30, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said peripheral edges and having inner ends diametrically opposed with respect to said bearing surface axis, and a third finger supported on said plate members, said third finger extending downwardly from said peripheral edges and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom.

34. An inductor assembly according to claim 33, wherein each said finger includes a shoe member fastened between said inner surfaces of said plate members, said inner and lower ends of said fingers each including a circular recess in the corresponding shoe member parallel to said axis, and an insert in said recess for engaging said bearing surface.

35. An inductor assembly according to claim 29, further including means supported on said plate members for directing quenching liquid toward said bearing surface.

36. An inductor assembly according to claim 35, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, said arcuate inductor legs being radially inwardly adjacent said peripheral edges, and said means for directing quenching liquid including means between said inner sides of said plate members at said lower ends thereof for directing quenching liquid laterally inwardly of said peripheral edges.

37. An inductor assembly according to claim 29, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, said arcuate inductor legs being radially inwardly adjacent said peripheral edges, said inner sides of said plate members at said lower ends including quenching liquid chamber means opening laterally inwardly of said peripheral edges, and quenching liquid distributor plate means in said chamber means for directing quenching liquid toward said bearing surface.

38. An inductor assembly according to claim 37, and quenching liquid supply conduit means for delivering quenching liquid to said chamber means, said conduit means having inlet end means clampingly engaged between said plate members.

39. An inductor assembly according to claim 38, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said peripheral edges and having inner ends diametrically opposed with respect to said bearing surface axis, a third finger supported on said plate members, said third finger extending downwardly from said peripheral edges and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom, said inner sides of said plate members including pocket means receiving said third finger, and means including tube means connected to said supply conduit means and extending therefrom between said plate members toward said pocket means for delivering liquid thereto to cool said third finger.

40. An inductor assembly according to claim 29, wherein said inductor means includes inductor block means having axially opposite sides, laterally extending top edge means between said sides and upwardly extending laterally spaced outer edge means between said sides, said recess means including opposed recesses receiving said inductor block means therebetween, and said support member means including shell means of insulating material in said opposed recesses and covering said opposite sides and said top and outer edge means of said inductor block means.

41. An inductor assembly according to claim 40, wherein said top end of said inductor means includes first and second tubular conductors connected to and extending upwardly from said top edge means of said inductor block means through said shell means and having axially outer sides generally coplanar with said opposite sides of said block means, said recess means including opposed recesses receiving said conductors, said conductors having upper ends including said means for connecting said inductor means to a source of power, said plate members having upper ends, said recess means including opposed recesses in said upper ends of said members, and said support member means further including block members of insulating material in said recesses in said upper ends of said plate members, said block members clampingly engaging said upper ends of said conductor therebetween.

42. An inductor assembly according to claim 41, wherein said inductor block means and said arcuate inductor legs have coolant flow passageway means therethrough in flow communication with said tubular conductors at said top edge means of said inductor block means.

43. An inductor assembly according to claim 42, wherein said coolant flow passageway means includes first and second coolant passageways having inlet ends for connection to a source of coolant and having outlet ends respectively communicating with said first and second conductors at said top edge means of said inductor block means.

44. An inductor assembly according to claim 43, wherein said inlet ends of said coolant passageways open through said outer edge means of said inductor block means, and coolant inlet conduit means connected to said outer edge means in flow communication with said inlet ends and having outer end means for connection to said source of coolant.

45. An inductor assembly according to claim 44, wherein said inlet ends open through a common one of said outer edge means and said inlet conduit means includes a tubular conduit in flow communication with both said inlet ends and extending laterally outwardly from said inductor block means parallel to said axially opposite sides thereof, said recess means including opposed recesses for said conduit, and said support member means further including support blocks of insulating material in said recesses for said conduit and clampingly engaging said conduit therebetween.

46. An inductor assembly according to claim 45, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, said arcuate inductor legs being radially inwardly adjacent said peripheral edges, said inductor means including lug means extending laterally outwardly from said inductor legs, said recess means including lug receiving recess means extending between said plate members from said peripheral edges, said support member means including lug clamping member means, and means fastening said lug clamping member means to said plate members and to said lug means.

47. An inductor assembly according to claim 46, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said peripheral edges and having inner ends diametrically opposed with respect to said bearing surface axis, a third finger supported on said plate members, said third finger extending downwardly from said peripheral edges and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom, each said finger including a shoe member fastened between said inner surfaces of said plate members, said inner and lower ends of said fingers each including a circular recess in the corresponding shoe member parallel to said axis and an insert in said recess for engaging said bearing surface.

48. An inductor assembly according to claim 47, wherein said inner sides of said plate members at said lower ends include quenching liquid chamber means opening laterally inwardly of said peripheral edges, quenching liquid distributor plate means in said chamber means for directing quenching liquid toward said bearing surface, and quenching liquid supply conduit means for delivering quenching liquid to said chamber means, said conduit means having inlet end means clampingly engaged between said plate members, said inner sides of said plate members including pocket means receiving said third finger, and means including tube means connected to said supply conduit means and extending therefrom between said plate members toward said pocket means for delivering liquid thereto to cool said third finger.

49. An inductor assembly for inductively heating a crankshaft bearing surface having an axis, said inductor assembly comprising inductor means having top and bottom ends, said bottom end of said inductor means including arcuate inductor legs facing said bearing surface, said top end including means for connecting said inductor means to a source of electrical power, and support means for said inductor means, said support means including plate members having inner surfaces, said inductor means being between said inner surfaces, and said support means further including support member means of insulating material clampingly engaging said inductor means between said plate members in spaced relationship thereto.

50. An inductor assembly according to claim 49, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said axis and having inner ends diametrically opposed with respect to said axis, and a third finger supported on said plate members, said third finger extending downwardly and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom.

51. An inductor assembly according to claim 50, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, said arcuate inductor legs being radially inwardly adjacent said peripheral edges, means between said inner sides of said plate members at said lower ends thereof for directing quenching liquid laterally laterally inwardly of said peripheral edges.

52. An inductor assembly according to claim 51, wherein said means for directing quenching liquid includes quenching liquid chamber means opening laterally inwardly of said peripheral edges, and quenching liquid distributor plate means in said chamber means for directing quenching liquid toward said bearing surface.

53. An inductor assembly according to claim 52, and quenching liquid supply conduit means for delivering quenching liquid to said chamber means, said conduit means having inlet end means clampingly engaged between said plate members by said support member means.

54. An inductor assembly according to claim 53, wherein said top end of said inductor means include first and second tubular conductors connected to and extending upwardly from said bottom end of said inductor means between said plate members, said conductors having upper ends including said means for connecting said inductor means to a source of power, and said support member means further including block members of insulating material between said upper ends of said plate members, said block members clampingly engaging said upper ends of said conductor therebetween.

61. An inductor assembly according to claim 51, and means between said inner sides of said plate members at said lower ends thereof for directing quenching liquid laterally inwardly of said peripheral edges.

62. An inductor assembly according to claim 61, wherein said means for directing quenching liquid includes quenching liquid chamber means opening laterally inwardly of said peripheral edges, quenching liquid distributor plate means in said chamber means for directing quenching liquid toward said bearing surface.

63. An inductor assembly according to claim 62, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said peripheral edges and having inner ends diametrically opposed with respect to said bearing surface axis, a third finger supported on said plate members, said third finger extending downwardly from said peripheral edges and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom, said inner sides of said plate members including pocket means receiving said third finger, and said inner sides including opposed recess means between said quenching liquid chamber means and said pocket means for delivering liquid to said pocket means to cool said third finger.

64. An inductor assembly according to claim 63, wherein said support means further includes pin means extending through said plate members and said inductor means to position said inductor means relative to said plate members.

55. An inductor assembly for inductively heating a crankshaft bearing surface having an axis, said inductor assembly comprising inductor means having top and bottom ends, said bottom end of said inductor means including arcuate inductor legs facing said bearing surface, said top end including means for connecting said inductor means to a source of electrical power, and support means for said inductor means, said support means including plate members of insulating material having outer surfaces transverse to said axis and having axially opposed inner surfaces including first and second inner surface portions, said first inner surface portions being in facial engagement with one another and said second inner surface portions including means providing recess means for receiving and clampingly engaging inductor means between said plate members.

56. An inductor assembly according to claim 55, wherein said support means further includes pin means extending through said plate members and said inductor means to position said inductor means relative to said plate members.

57. An inductor assembly according to claim 55, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, and said arcuate inductor legs being radially inwardly adjacent said peripheral edges.

58. An inductor assembly according to claim 57, wherein said inductor means includes lug means extending laterally outwardly from said inductor legs, and said recess means includes lug receiving recess means extending between said plate members from said peripheral edges.

59. An inductor assembly according to claim 57, wherein said support means further includes pin means extending through said plate members and said inductor means to position said inductor means relative to said plate members.

60. An inductor assembly according to claim 59, wherein said pin means includes pin members extending through said lug means.

65. An inductor assembly according to claim 55, wherein said inductor means includes inductor block means having axially opposite sides and upper and lower ends, said upper end having laterally extending top edge means between said sides and upwardly extending laterally spaced outer edge means between said sides, said inductor legs extending laterally outwardly from said outer edge means at said lower end, said recess means including opposed recesses receiving said upper end of said inductor block means therebetween, and said support member means including pin means extending through said plate members and said inductor block means to position said inductor block means relative to said plate members.

66. An inductor assembly according to claim 65, wherein said pin means includes a plurality of pins extending through said upper end of said inductor block means.

67. An inductor assembly according to claim 66, wherein said plate members have upper and lower ends and inverted generally U-shaped openings axially through said lower ends, said openings having peripheral edges, said arcuate inductor legs being radially inwardly adjacent said peripheral edges, said lower end of said inductor block means including a mounting lug extending laterally outwardly from each said inductor leg, said recess means including opposed lug receiving recesses for each said lug and clampingly engaging said lug therebetween, and said pin means including a pin extending through each said lug.

68. An inductor assembly according to claim 67, wherein said inductor means includes first and second tubular conductors connected to and extending upwardly from said top edge means of said inductor block means and having axially outer sides generally coplanar with said opposite sides of said inductor block means, said recess means including opposed recesses receiving said conductors, said conductors having upper ends including said means for connecting said inductor means to a source of power, said recess means including opposed recesses in said upper ends of said plate members clampingly engaging said upper ends of said conductor therebetween.

69. An inductor assembly according to claim 68, wherein said inductor block means and said arcuate inductor legs have coolant flow passageway means therethrough, said coolant flow passageway means including first and second coolant passageways having inlet ends for connection to a source of coolant and having outlet ends respectively communicating with said first and second tubular conductors at said top edge means of said inductor block means said inlet ends of said coolant passageways opening through a common one of said outer edge means of said inductor block means, a tubular coolant inlet conduit connected to said one outer edge means in flow communication with both said inlet ends and having outer end means for connection to said source of coolant, said tubular conduit extending laterally outwardly from said inductor block means parallel to said axially opposite sides thereof, said recess means including a recess for said conduit in said inner surface of one of said plate members, and said recess and said inner surface of the other of said plate members clampingly engaging said conduit therebetween.

70. An inductor assembly according to claim 69, wherein said support means further includes a pair of fingers supported on said plate members, said pair of fingers extending laterally inwardly of said peripheral edges and having inner ends diametrically opposed with respect to said bearing surface axis, a third finger supported on said plate members, said third finger extending downwardly from said peripheral edges and having a lower end vertically aligned with said axis, said inner and lower ends being positioned to engage said bearing surface and space said inductor legs therefrom, said inner sides of said plate members including pocket means receiving said third finger, and said inner sides including opposed recess means between said quenching liquid chamber means and said pocket means for delivering liquid to said pocket means to cool said third finger.