Induction hardening apparatus, induction hardening method, induction heating coil, heat treatment apparatus, and heat treatment method

Patent metadata

Field	Value
Publication number	US-9534267-B2
Application number	US-201213360274-A
Country	US
Kind code	B2
Filing date	Jan 27, 2012
Priority date	Jul 30, 2009
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

According to an embodiment, an induction heating coil includes a heating conductor portion which is formed of a conductor member and has a zigzag shape in which a bent portion opened to one side in a first direction and a bent portion opened to the other side in the first direction are alternately continuously arranged in opposite directions along a second direction crossing the first direction.

First claim

What is claimed is:

1. An induction hardening apparatus, comprising:
heating coils disposed around a treatment object having a peripheral surface as a treatment target portion;
the treatment object and the heating coils being relatively moved along a circumferential direction of the treatment target portion of the treatment object based on rotational movement of at least one of the treatment object and each of the heating coils;
the treatment target portion of the treatment object being inductively heated;
a stepped peripheral surface with a concave portion aligned along a circumferential direction and a convex portion aligned along a circumferential direction of the treatment object being determined as the treatment target portion; and
the heating coils comprising:
a first heating coil which is arranged to face a peripheral surface region of the concave portion of the treatment object and is configured to inductively heat the concave portion of the treatment object; and
a second heating coil which is arranged to face a peripheral surface region of the convex portion of the treatment object and is configured to inductively heat the convex portion of the treatment object;

at least one of the heating coils comprising a heating conductor portion having a zigzag shape in which a bent portion that is aligned along a circumferential direction of the rotation and is opened to one side in an axial direction of the rotation and a bent portion that is arranged along a circumferential direction of the rotation and is opened to the other side in the axial direction are alternately continuously arranged side by side along the circumferential direction, wherein the first heating coil and the second heating coil are spaced from each other and adjacently arranged in the circumferential direction of the treatment object.

2. The apparatus according to claim 1 ,
wherein an interval between the bent portions adjacent to each other is one times or above and two times or below a width dimension of the heating conductor portion.

3. The apparatus according to claim 1 ,
wherein at least one of the heating coils comprises a heating conductor portion that extends to cross the circumferential direction of the rotation and has a configuration such that a length in the circumferential direction of a part apart from the center of rotational movement is larger than a length in the circumferential direction of a part close to the center.

4. The apparatus according to claim 3 ,
wherein the heating conductor portion has a fixed cross-sectional area and is bent in such a manner that an extension angle of the part apart from the center with respect to the circumferential direction becomes smaller than an extension angle of the part close to the center.

5. The apparatus according to claim 1 ,
wherein a dimension of the heating coils in the circumferential direction is not smaller than 1/10 and not greater than 1/2 of a dimension of the treatment target portion in the circumferential direction.

6. The apparatus according to claim 1 ,
wherein the treatment target portion is formed into an endless loop-like continuous shape along the circumferential direction.

7. The apparatus according to claim 1 ,
wherein the treatment object has a drum-like shape.

8. The apparatus according to claim 1 ,
wherein the treatment object is a hollow body and has an inner peripheral surface formed to be inclined with respect to the axial direction and the circumferential direction.

9. The apparatus according to claim 1 ,
wherein respective regions of the treatment target portion heated by the heating conductor portions of the heating coils form one continuous heating region.

10. The apparatus according to claim 1 , comprising a cooling unit which performs a cooling treatment for the treatment target portion after the heat treatment is performed by the heating coils in a whole stroke of the treatment target portion in the circumferential direction.

11. The apparatus according to claim 1 , wherein at least one of the heating coils comprises a heating conductor portion having a rectangular frame shape.

12. An induction hardening apparatus, comprising:
heating coils disposed around a treatment object having a peripheral surface as a treatment target portion;
the treatment object and the heating coils being relatively moved along a circumferential direction of the treatment target portion of the treatment object based on rotational movement of at least one of the treatment object and each of the heating coils;
the treatment target portion of the treatment object being inductively heated;
a stepped peripheral surface with a concave portion aligned along a circumferential direction and a convex portion aligned along a circumferential direction of the treatment object being determined as the treatment target portion; and
the heating coils comprising:
a first heating coil which is arranged to face a peripheral surface region of the concave portion of the treatment object and is configured to inductively heat the concave portion of the treatment object; and
a second heating coil which is arranged to face a peripheral surface region of the convex portion of the treatment object and is configured to inductively heat the convex portion of the treatment object;
at least one of the heating coils comprising a heating conductor portion having a zigzag shape in which a bent portion that is aligned along a circumferential direction of the rotation and is opened to one side in an axial direction of the rotation and a bent portion that is arranged along a circumferential direction of the rotation and is opened to the other side in the axial direction are alternately continuously arranged side by side along the circumferential direction, wherein the first heating coil and the second heating coil are spaced from each other and alternately arranged in the circumferential direction of the treatment object.

13. The apparatus according to claim 12 ,
wherein an interval between the bent portions adjacent to each other is one times or above and two times or below a width dimension of the heating conductor portion.

14. The apparatus according to claim 12 ,
wherein at least one of the heating coils comprises a heating conductor portion that extends to cross the circumferential direction of the rotation and has a configuration such that a length in the circumferential direction of a part apart from the center of rotational movement is larger than a length in the circumferential direction of a part close to the center.

15. The apparatus according to claim 14 ,
wherein the heating conductor portion has a fixed cross-sectional area and is bent in such a manner that an extension angle of the part apart from the center with respect to the circumferential direction becomes smaller than an extension angle of the part close to the center.

16. The apparatus according to claim 12 ,
wherein a dimension of the heating coils in the circumferential direction is not smaller than 1/10 and not greater than 1/2 of a dimension of the treatment target portion in the circumferential direction.

17. The apparatus according to claim 12 ,
wherein the treatment target portion is formed into an endless loop-like continuous shape along the circumferential direction.

18. The apparatus according to claim 12 ,
wherein the treatment object has a drum-like shape.

19. The apparatus according to claim 12 ,
wherein the treatment object is a hollow body and has an inner peripheral surface formed to be inclined with

Assignees

• Tanaka Yoshimasa
• Misaka Yoshitaka
• Asano Yuji
• Neturen Co Ltd

Inventors

• Tanaka Yoshimasa
• Misaka Yoshitaka
• Asano Yuji

Classifications

• H05B6/36 Primary

  Coil arrangements · CPC title

• H05B6/102

  the metal pieces being rotated while induction heated · CPC title

• C21D2221/00

  Treating localised areas of an article · CPC title

• C21D9/40 Primary

  for rings; for bearing races · CPC title

• C21D1/42

  Induction heating · CPC title