JP5378000B2 - Induction heating coil manufacturing method for induction hardening of engine crankshaft and induction heating coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an induction heating coil used for induction hardening of the crankshaft for an engine and an induction heating coil, prevented in deterioration of the product quality with excellent in product service life. <P>SOLUTION: The method of manufacturing an induction heating coil includes: a first processing step S100 of boring groove parts 80a, etc. having a predetermined shape in a plurality of preforms 60-64 made of a base material of an induction heating coil body 10 to form a cooling water passage 5 as a whole by combining the preforms 60-64 on joining surfaces 60a, etc.; a joining step S110 of forming one molded body 6 by respectively combining the preforms 60-64 having the groove parts 80a, etc. bored in the first processing step S100 on predetermined joining surfaces 60a, etc. and joining the joining surfaces 60a, etc. of the preforms 60-64 by solid-phase welding; and a second processing step S120 of shaving the induction heating coil body 10 based on the shape of the groove parts 80a, etc. with respect to the molded body 6 joined in the joining step S110. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  TECHNICAL FIELD The present invention relates to an induction heating coil manufacturing method and induction heating coil technology, and more particularly, to an induction heating coil manufacturing method used for induction hardening of an engine crankshaft, which has a cooling water passage for flowing cooling water therein. And to the technology of induction heating coils.

  2. Description of the Related Art Conventionally, a configuration of an induction hardening apparatus that heats an object to be heated such as a steel member to a predetermined quenching temperature using induction heating and rapidly cools the object is known. In such an induction hardening apparatus, in general, in order to induction-heat the outer peripheral surface or inner peripheral surface of the object to be heated, induction having a heating conductor portion formed along the shape of the object to be heated (such as an outer peripheral shape). A heating coil is used. Examples of the object to be heated include various shapes such as a shaft-like member such as a crankshaft for an automobile engine, and the induction heating coil is variously configured according to the shape of the object to be heated.

  As a configuration of the induction heating coil, generally, a linear or curved heating conductor portion is connected between a pair of lead conductor portions connected to a high-frequency power source, and the outer periphery of the object to be heated described above as a whole. It is formed as a structure partly extended, bent or curved along the shape. In addition, a cooling water flow path for flowing cooling water is provided inside the lead conductor part and the heating conductor part, and the cooling water always flows through the cooling water flow path at the time of induction heating. It is configured to prevent damage due to overheating.

  For example, as disclosed in Patent Documents 1 to 3, these conventional induction heating coils include a pipe member in which a lead conductor part and a heating conductor part are formed of a conductive material such as copper into a pipe shape having a substantially rectangular cross section. The pipe member is connected by brazing so that the heating conductor portion has a predetermined shape as a whole. In particular, in an induction heating coil, a plurality of bent portions are often formed in the connection portion between the lead conductor portion and the heating conductor portion or in the heating conductor portion. First, a plurality of pipe members having a rectangular cross section are formed, and then the end portions of the pipe members are connected by brazing at bent portions constituting the heating conductor portion.

  By the way, the induction heating coil used in the induction hardening apparatus generates an alternating magnetic flux by flowing an alternating high frequency current supplied from a high frequency power supply during quenching, and an eddy current is generated in the object to be heated by the alternating magnetic flux. The object to be heated is heated by the resistance heat generated by the eddy current generated in the object to be heated and the heat generated by the hysteresis loss due to the alternating magnetic flux from the induction heating coil. Further, at the time of quenching, since the induction heating coil is heated to a high temperature by the radiant heat from the heated object to be heated, the cooling water is constantly flowing through the cooling water flow path as described above.

  However, in the conventional induction heating coil configuration, since the high-frequency current supplied from the high-frequency power source is concentrated on the bent portion as compared with other parts, the temperature of the bent portion is locally increased by repeated energization by quenching. It rises or the temperature amplitude due to heating / cooling becomes larger in the bent part than in other parts. For this reason, the brazing material itself may deteriorate (shrinkage and bubble generation), which may reduce the bonding strength of the brazed part or peel off the brazed part, resulting in a reduction in product quality at the connecting part of the bent part. There was a problem that the product life of the induction heating coil was inferior.

  In particular, in an induction heating coil used for induction hardening of a crankshaft for an engine of an automobile or the like, there are many precision brazing points and brazing points (joining points) are close in the conventional manufacturing method by brazing. Therefore, mature skills are required, and there is a problem in that the product quality varies depending on the skill level of the operator.

  Also, in recent years, induction heating coils have become more complicated and refined according to the shape of the object to be heated in order to reduce the unevenness of heating to the object to be heated and to improve the quenching accuracy by homogenizing the quenching depth. Tend to be configured into different shapes. Along with the complexity of the shape of the induction heating coil, a plurality of bent portions are formed in the induction heating portion, so that the problem that the product quality is reduced at the joint portion of the bent portion has become more serious. ing.

  From the above viewpoint, Patent Document 3 proposes a configuration of an induction heating coil in which the cross-sectional shape of at least one pipe member connected at the bent portion is a polygonal cross section having apexes between the corner portions of the bent portion. ing. However, even with such an induction heating coil configuration, the pipe member having such a cross-sectional shape is connected by brazing in the conventional induction heating coil manufacturing method, and thus the above-described problems still remain. It remained.

JP-A-8-283862 JP 2004-52013 A JP 2006-302683 A

  Therefore, the present invention relates to an induction heating coil manufacturing method used for induction hardening of an engine crankshaft and an induction heating coil, which solves the above-mentioned conventional problems, prevents a reduction in product quality, and has an excellent product life. An induction heating coil manufacturing method used for induction hardening of an engine crankshaft and an induction heating coil are provided.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

The invention according to claim 1 is a lead conductor portion extending in the horizontal direction, a heating conductor portion connected to one end of the lead conductor portion and formed in a curved shape in the horizontal direction, the lead conductor portion and the heating conductor. An induction heating coil used for induction hardening of a crankshaft for an engine having a cooling water flow path for flowing cooling water inside the part, and passing through a bent portion formed in the lead conductor portion and the heating conductor portion When the induction heating coil is divided into a plurality of divided layer portions in a plurality of pseudo planes that are parallel to the horizontal direction of the induction heating coil, the shape of the cooling water flow path appears in the plane cross section of the divided layer portion. Based on the first processing step , each of which is formed by a base material of the induction heating coil and the corresponding number of groove portions are formed on the joint surfaces of the preformed body with the same number of the divided layer portions. Groove is drilled The pre-molded bodies are respectively combined at the joining surfaces, and the joining step of joining the pre-formed bodies by solid phase joining to form one molded body, and the molded body joined in the joining step And a second processing step of scraping the induction heating coil based on the shape of the groove.

In Claim 2 , the said joining process combines a part of the said cooling water flow path by combining the said groove part drilled in the predetermined preform, and the said groove part drilled by the corresponding preformed body. The preform is positioned so that is formed.

In Claim 3 , It is an induction heating coil used for induction hardening of the crankshaft for engines manufactured by the manufacturing method of the induction heating coil as described in any one of the said Claim 1 thru | or 5, Comprising: Bending part It is continuous continuously without being brazed.

  As an effect of the present invention, it is possible to manufacture an induction heating coil that is used for induction hardening of an engine crankshaft that prevents a reduction in product quality and has an excellent product life.

The perspective view which showed the whole structure of the induction heating coil which concerns on one Example of this invention. The perspective view which showed the structure of the induction heating coil body. The flowchart which showed the manufacturing method of the induction heating coil. The perspective view which showed the state which assembled | attached the preforming body by which the groove part was pierced. The side view which showed a mode that the induction heating coil body was divided | segmented in a horizontal surface. The perspective view which showed the structure of the division layer part. The top view which showed the shape of the groove part drilled in a preforming body. The top view which showed the shape of the groove part similarly drilled in a preforming body. The top view which showed the shape of the groove part similarly drilled in a preforming body. The top view which showed the shape of the groove part similarly drilled in a preforming body. The top view which showed the shape of the groove part similarly drilled in a preforming body.

Below, the form for inventing is demonstrated.
In the following examples, the arrow X direction shown in FIG. 1 is the vertical direction of the induction heating coil 1 (induction heating coil body 10), and the arrow Y direction shown in FIG. 1 is the induction heating coil 1 (induction heating coil body 10). ) In the horizontal direction.

First, the overall configuration of the induction heating coil 1 manufactured by the manufacturing method of the present embodiment will be outlined below.
As shown in FIG. 1, the induction heating coil 1 of the present embodiment is connected to an induction hardening apparatus (not shown), and an object 2 such as a steel member is heated to a predetermined quenching temperature by using induction heating. It is used as a coil member for quenching (or tempering) by heating and quenching. The induction heating coil 1 of this embodiment is configured as a coil member used for induction hardening of an engine crankshaft of an automobile or the like, and the object to be heated 2 is mainly intended for an engine crankshaft of an automobile or the like. The outer peripheral surface of the engine crankshaft is induction-heated by the induction heating coil 1.

  The induction heating coil 1 of the present embodiment is configured as a pair of induction heating coil bodies 10 and 10 formed in a substantially symmetrical shape along the axial center direction of the object to be heated 2. The induction heating coil bodies 10 and 10 are configured so that pipe members formed in a pipe shape having a rectangular cross section with a copper material as a conductive material respectively follow the outer peripheral shape (outer peripheral surface) of the object to be heated 2. It is formed as an extended, bent or curved structure.

  In the following embodiments, since the induction heating coil bodies 10 and 10 are formed in a substantially symmetrical shape, the configuration of one induction heating coil body 10 will be described unless otherwise specified, and the other The detailed description of the configuration of the induction heating coil body 10 will be omitted.

Next, the configuration of the induction heating coil body 10 will be described in detail below.
As shown in FIGS. 1 and 2, the induction heating coil body 10 of this embodiment includes a pair of lead conductor portions 3 connected to a high-frequency power source (not shown) provided in the induction hardening apparatus, and a lead conductor portion 3. The heating conductor portion 4 and the like are connected and formed in a curved shape so as to follow the outer peripheral shape of the object to be heated 2. The induction heating coil body 10 is formed in a substantially symmetrical shape in the vertical direction with respect to a horizontal plane passing through the center position in the vertical direction.

  The lead conductor portion 3 is constituted by a pipe member having a substantially rectangular cross section formed in a substantially straight shape, one end is connected to a high frequency power source (not shown), and the other end is connected to a heating conductor portion 4 described later. Yes. In particular, the lead conductor portion 3 of the present embodiment is composed of a pair of pipe members extending in the horizontal direction, and an upper lead conductor portion 30a disposed above and a lower lead conductor portion disposed below. 30b are arranged in parallel so as to have a predetermined separation in the vertical direction of the induction heating coil 1.

  The upper lead conductor portion 30a and the lower lead conductor portion 30b are formed in substantially the same shape, and the heating conductor portion 4 described later is connected between the upper lead conductor portion 30a and the lower lead conductor portion 30b. The high-frequency current supplied from the high-frequency power source to the lead conductor portion 3 flows to the heating conductor portion 4 via the upper lead conductor portion 30a in the induction heating coil body 10, and flows along the shape of the heating conductor portion 4. Return to the high frequency power source from the lower lead conductor portion 30b.

  The heating conductor portion 4 is connected to one end of the lead conductor portion 3 (the upper lead conductor portion 30a and the lower lead conductor portion 30b), and is formed in a curved shape in the horizontal direction along the outer peripheral shape of the object to be heated 2. It consists of a pipe member. Specifically, a pair of bending portions 40 (an upper bending portion 40a and a lower bending portion 40b) that extend in a curved shape in the horizontal direction and are arranged in parallel so as to have a predetermined separation in the vertical direction, and the bending portion 40 (upper bend portion 40a and lower bend portion 40b) one end side of the upper and lower connecting portion 41 is connected in the vertical direction, and the other end side of bend portion 40 (upper bend portion 40a and lower bend portion 40b) is the upper lead conductor portion. 30a and the lower lead conductor part 30b, respectively, and a connection part 42 (upper connection part 42a and lower connection part 42b) to be connected.

  The induction heating coil body 10 of the present embodiment includes an upper bending portion 40a and a lower bending portion 40b, a vertical connection portion 41, a heating conductor portion 4 having an upper connection portion 42a and a lower connection portion 42b, and the above-described upper lead. A lead conductor portion 3 having a conductor portion 30a and a lower lead conductor portion 30b is continuously and integrally formed. That is, in the induction heating coil body 10, in the lead conductor portion 3 and the heating conductor portion 4, the upper curved portion 40a is continued to the upper lead conductor portion 30a via the upper connecting portion 42a, and the lower connecting portion is connected to the lower lead conductor portion 30b. The lower bending portion 40b is continued through 42b, and the upper bending portion 40a and the lower bending portion 40b are connected to the upper connection portion 42a and the lower connection portion 42b at the opposite end via the upper and lower connection portions 41. And are integrally formed.

  The upper bending portion 40a and the lower bending portion 40b are curved while extending in the horizontal direction of the induction heating coil body 10 so as to follow the outer peripheral shape of the article 2 to be heated, and are separated by a predetermined distance in the vertical direction of the induction heating coil body 10. Are arranged side by side. Moreover, the edge part which is a curved surface of the upper curved part 40a and the lower curved part 40b, and opposes the to-be-heated material 2 is protruded in the direction which adjoins the to-be-heated material 2. FIG. At the time of quenching, an eddy current is generated in the object to be heated by the alternating magnetic flux generated by the high-frequency current flowing through the bending part 40. Therefore, by bringing the edge close to the outer peripheral shape of the object to be heated 2, the bending part The quenching efficiency can be improved at 40.

  The vertical connecting portion 41 is formed of a substantially long plate-like pipe member extending in the vertical direction, and has an end opposite to the end on the upper lead conductor portion 30a side of the upper bending portion 40a, and a lower bending portion. 40b is formed so as to connect the end portion on the opposite side to the end portion on the lower lead conductor portion 30b side, and in this embodiment, the upper and lower connecting portion 41 includes the upper bending portion 40a and the lower bending portion 40b. It connects so that it may contact | abut with respect to the edge part from a horizontal direction.

  The upper connection portion 42a and the lower connection portion 42b are configured by a pipe member having a rectangular cross section, one end of which is formed in substantially the same shape as the end portions of the upper lead conductor portion 30a and the lower lead conductor portion 30b. Specifically, the upper connection portion 42a is continuous with the end portion of the upper lead conductor portion 30a, and the upper curved portion 40a extends in the horizontal direction along the outer peripheral shape of the article to be heated 2 on the upper surface side of the upper connection portion 42a. It is continued as it is issued. On the other hand, the lower connection portion 42b is continuous with the end portion of the lower lead conductor portion 30b, and the lower curved portion 40b extends horizontally along the outer peripheral shape of the article to be heated 2 on the lower surface side of the lower connection portion 42b. Is continuous.

  The induction heating coil body 10 of the present embodiment as a whole extends from the upper lead conductor portion 30a extending in the horizontal direction toward the radial direction of the object to be heated 2 to the upper connection part 42a. The upper bent portion 40a is bent by the upper and lower connecting portions 41 from the upper curved portion 40a which is bent upward and circumferentially above the heated object 2 and extends and curved in the horizontal direction along the outer peripheral shape of the heated object 2. It is bent in the direction. Similarly, from the lower lead conductor part 30b extending in the horizontal direction toward the radial direction of the object to be heated 2 with respect to the object to be heated 2, the lower connection part 42b is below the object to be heated 2 and in the circumferential direction. And bent upwardly at the upper and lower connecting portions 41 from the lower curved portion 40b extending and curved in the horizontal direction along the outer peripheral shape of the article 2 to be heated.

  By being configured in this manner, the induction heating coil body 10 of the present embodiment is formed with the bent portion 10a at the upper connection portion 42a that is a connection portion between the upper lead conductor portion 30a and the upper curved portion 40a. A bent portion 10b is formed at a connection portion between the upper curved portion 40a and the upper and lower connecting portion 41, and a bent portion 10c is formed by the connection portion between the lower curved portion 40b and the upper and lower connecting portion 41, and the lower lead conductor portion 30b. A bent portion 10d is formed at a lower connection portion 42b which is a connection portion between the lower bending portion 40b and the lower bending portion 40b.

Here, the configuration of the cooling water passage 5 formed in the induction heating coil body 10 will be described in detail below.
As shown in FIG. 2, the induction heating coil body 10 of the present embodiment is made of a pipe member having a rectangular cross section made of a copper material, thereby forming a cooling water passage 5 through which cooling water flows. . The cooling water flow path 5 is formed continuously in the hollow inside of the pipe member constituting the lead conductor portion 3 and the heating conductor portion 4, and the cooling water supplied to the upper lead conductor portion 30a from a cooling water tank (not shown). Flows in the order of the upper lead conductor portion 30a → the upper connection portion 42a → the upper bending portion 40a → the vertical coupling portion 41 → the lower bending portion 40b → the lower connection portion 42b → the lower lead conductor portion 30b. Discharged outside.

  Specifically, the cooling water flow path 5 includes an upper flow path 50a and a lower flow path 50b that extend linearly along the horizontal direction inside the upper lead conductor portion 30a and the lower lead conductor portion 30b, and an upper curved portion. The upper flow path 51a and the lower flow path 51b extending in a curved shape along the horizontal direction in the hollow inside of the lower bending portion 40b and the lower bending portion 40b and the hollow inside of the upper and lower connection portion 41 are extended linearly along the vertical direction. The upper and lower flow paths 52 are hollow inside the upper connection portion 42a and the lower connection portion 42b, and extend linearly along the horizontal direction on the connection side with the upper lead conductor portion 30a or the lower lead conductor portion 30b. On the other hand, it is composed of an upper flow path 53a and a lower flow path 53b that are bent upward or downward in the middle and extend linearly along the vertical direction on the connection side with the upper curved portion 40a or the lower curved portion 40b. Yes.

  As described above, the induction heating coil body 10 of the present embodiment is extended substantially in the horizontal direction by the upper lead conductor portion 30a, the lower lead conductor portion 30b, the upper curved portion 40a, and the lower curved portion 40b. The upper curved portion 40a is located at the uppermost position in the vertical direction, and the upper curved portion 40a, the upper lead conductor portion 30a, the lower lead conductor portion 30b, and the lower curved portion 40b. The lower curved portion 40b is located at the lowermost position. Therefore, as the cooling water flow path 5 of the induction heating coil body 10, the upper flow path 50a and the lower flow path 50b, and the upper flow path 51a and the lower flow path 51b are respectively extended in the horizontal direction. The upper channel 51a, the upper channel 50a, the lower channel 50b, and the lower channel 51b are positioned in this order.

Next, the manufacturing method of the induction heating coil 1 of a present Example is explained in full detail below.
In the following embodiments, the manufacturing method of one induction heating coil body 10 will be mainly described as a manufacturing method of the induction heating coil 1, but the same applies to the manufacturing method of the other induction heating coil body 10.

  The method of manufacturing the induction heating coil body 10 of this embodiment is a method of integrally forming the induction heating coil body 10 without being brazed at the bent portions 10a to 10d in the lead conductor portion 3 and the heating conductor portion 4. The induction heating coil body 10 is manufactured by cutting out from the molded body 6 made of the base material of the induction heating coil body 10. In particular, in the induction heating coil body 10 of the present embodiment, since the cooling water flow path 5 is formed in the hollow interior, a plurality of preformed bodies 60 to 64 are previously drilled with a groove portion 80a having a predetermined shape. In addition, a space corresponding to the cooling water flow path 5 is formed inside the molded body 6 by combining the preformed bodies 60 to 64 with the corresponding joint surfaces 60a to form one molded body 6. It is said.

  Specifically, as shown in FIG. 3, the method of manufacturing the induction heating coil body 10 according to the present embodiment includes a plurality of preformed bodies 60 to 64 made of the base material of the induction heating coil body 10. To 64 are combined with the joint surface 60a or the like to form the groove portion 80a having a predetermined shape so that the cooling water flow path 5 is formed as a whole, and the groove portion 80a or the like in the first processing step S100. Are formed by combining the preformed bodies 60 to 64 each having a hole formed therein with a predetermined joining surface 60a and the like, and joining the joining surfaces 60a and the like of the preformed bodies 60 to 64 by solid phase joining. It has process S110 and 2nd process process S120 which scrapes the induction heating coil body 10 based on the shape of the groove part 80a etc. with respect to the molded object 6 joined by joining process S110.

  First, as shown in FIG. 4, the preforms 60 to 64 used in the first processing step S <b> 100 are flat plate-like members having a rectangular shape in plan view made of the base material of the induction heating coil body 10, and in the upper and lower planes. Each has a horizontal plane and is formed in substantially the same shape. In this embodiment, five preformed bodies 60 to 64 are used, and the preforms 60 to 64 are formed so that their thicknesses (vertical heights) are substantially the same. As will be described later, the induction heating coil body 10 is divided into divided layer portions 11 to 15 having the same number as the preformed bodies 60 to 64 and the same thickness (see FIG. 5).

  The preformed bodies 60 to 64 are assembled as one molded body 6 having a rectangular parallelepiped shape by being combined with the joining surface 60a or the like in the vertical direction in a joining step S110 described later. In the present embodiment, the preform 60 is disposed at the uppermost position, and is located below in the order of the preform 60 → the preform 61 → the preform 62 → the preform 63 → the preform 64, The preformed body 64 is disposed at the lowest position.

  The preformed body 60 and the preformed body 61 are combined in a state in which the joining surface 60 a that is the lower horizontal surface of the preformed body 60 and the joining surface 61 b that is the upper horizontal surface of the preformed body 61 are in contact with each other. Similarly, the preformed body 61 and the preformed body 62 are combined in a state where the joint surface 61a that is the lower horizontal surface of the preformed body 61 and the joint surface 62b that is the upper horizontal surface of the preformed body 62 are in contact with each other. The preformed body 62 and the preformed body 63 are combined in a state where the joint surface 62a which is the lower horizontal surface of the preformed body 62 and the joint surface 63b which is the upper horizontal surface of the preformed body 63 are in contact with each other. 63 and the preformed body 64 are combined in a state in which the joint surface 63a which is the lower horizontal surface of the preformed body 63 and the joint surface 64b which is the upper horizontal surface of the preformed body 64 are in contact with each other.

  As shown in FIGS. 5 to 11, in the first processing step S <b> 100, grooves 80 a and the like having predetermined shapes are formed in the joint surfaces 60 a and the like of the preforms 60 to 64 described above. When the induction heating coil body 10 is divided into the divided layer parts 11 to 15 at a plurality of horizontal planes 70 to 73 parallel to the horizontal direction of the induction heating coil body 10, the groove part 80 a and the like are divided layer parts 11. It is set as the shape corresponding to the shape of the cooling water flow path 5 which appears in the plane cross section of -15.

  As shown in FIG. 5, specifically, the induction heating coil body 10 is first divided into five divided layer portions 11 to 15 having substantially the same thickness (vertical height) by four horizontal surfaces 70 to 73, respectively. Divided. The horizontal planes 70 to 73 are pseudo planes that are parallel to each other along the horizontal direction of the induction heating coil body 10, and pass through the bent portions 10 a to 10 d formed in the induction heating coil body 10 by the horizontal planes 70 to 73. In this way, the induction heating coil body 10 is divided.

  More specifically, the horizontal plane 70 is a pseudo plane that passes through the bent portion 10b formed at the connection portion between the upper curved portion 40a and the upper and lower connecting portion 41. Similarly, hereinafter, the horizontal plane 71 is a pseudo plane passing through the bent portion 10a formed at the connection portion (upper connection portion 42a) between the upper lead conductor portion 30a of the induction heating coil body 10 and the upper bending portion 40a. 72 is a pseudo plane passing through the bent portion 10c formed at the connecting portion between the lower curved portion 40b and the upper and lower connecting portion 41, and the horizontal surface 73 is a connecting portion (lower portion) between the lower lead conductor portion 30b and the lower curved portion 40b. This is a pseudo plane passing through the bent portion 10d formed in the connecting portion 42b).

  By dividing the induction heating coil body 10 in the horizontal direction by the horizontal planes 70 to 73 in this way, the induction heating coil body 10 is divided into five divided layer portions 11 to 15, and the plane cross section of the divided layer portions 11 to 15. The horizontal cross-sectional shape of the cooling water flow path 5 formed in the internal hollow part of the induction heating coil body 10 appears.

Referring to FIG. 6, the shapes appearing in the plane cross sections of the divided layer portions 11 to 15 in the present embodiment will be described. In the plane cross section that is the lower horizontal plane of the divided layer portion 11, the upper curved portion 40 a and the upper and lower connecting portions 41 are provided. The horizontal cross-sectional shapes of the upper flow path 51a and the vertical flow path 52 appear (see FIG. 6A).
Similarly, the horizontal cross-sectional shapes of the upper curved portion 40a, the upper and lower connecting portion 41, the upper connection portion 42a, the upper flow path 51a, the vertical flow path 52, and the upper flow path 53a appear in the flat cross section that is the upper horizontal plane of the dividing layer portion 12. (Refer to FIG. 6 (b).) The upper cross section 50a, the upper flow path 52, and the upper flow path 53a of the upper lead conductor portion 30a, the upper and lower connection portion 41, and the upper connection portion 42a are shown in the plane cross section as the lower horizontal surface of the dividing layer portion 12. The horizontal cross-sectional shape of appears.
The horizontal cross-sectional shape of the upper and lower flow paths 52 of the upper and lower connecting portions 41 appears in the flat cross section that is the upper horizontal plane of the divided layer portion 13, and the upper and lower ends of the upper and lower connecting portions 41 appear in the flat cross section that is the lower horizontal plane of the divided layer portion 13. A horizontal cross-sectional shape of the path 52 appears (see FIG. 6C).
The horizontal cross-sectional shapes of the lower lead conductor portion 30b, the upper and lower connecting portion 41, the lower connection portion 42b, the lower flow path 50b, the vertical flow path 52, and the lower flow path 53b appear in the flat cross section that is the upper horizontal plane of the divided layer portion 14. 6 (d)), the flat surface which is the lower horizontal surface of the divided layer portion 14 includes horizontal surfaces of the lower curved portion 40b, the upper and lower connecting portions 41, the lower connection portion 42b, the lower flow channel 51b, the vertical flow channel 52, and the lower flow channel 53b. A cross-sectional shape appears.
The horizontal cross-sectional shape of the lower curved portion 40b, the lower flow path 51b, and the vertical flow path 52 of the vertical connection portion 41 appears on the flat cross section that is the upper horizontal plane of the dividing layer portion 15 (see FIG. 6E).

  Next, in the first processing step S100, based on the horizontal cross-sectional shape of the cooling water flow path 5 that appears in the plane cross section of the divided layer portions 11 to 15 obtained by dividing the induction heating coil body 10 in the horizontal planes 70 to 73 in this way, Grooves 80a and the like having shapes corresponding to the joint surfaces 60a and the like of the preforms 60 to 64 described above are formed.

With reference to FIGS. 7 to 11, the shape of the groove portion 80 a and the like formed in the joint surface 60 a of the preformed bodies 60 to 64 in the present embodiment will be described. A groove 80a having a shape corresponding to the horizontal cross-sectional shape of the upper flow path 51a and the upper and lower flow paths 52 appearing in the plane cross section of the divided layer portion 11 is formed (see FIG. 7).
Similarly, a groove portion having a shape corresponding to the horizontal cross-sectional shape of the upper flow path 51a, the upper and lower flow paths 52, and the upper flow path 53a appearing in the flat cross section that is the upper horizontal plane of the divided layer portion 12 is formed on the joint surface 61b of the preformed body 61. 81b is drilled, and the joint surface 61a of the preformed body 61 corresponds to the horizontal plane cross-sectional shapes of the upper flow path 50a, the upper and lower flow paths 52, and the upper flow path 53a that appear in the flat cross section that is the lower horizontal plane of the divided layer portion 12. A groove 81a having a shape is formed (see FIG. 8).
A groove 82b having a shape corresponding to the horizontal cross-sectional shape of the up-and-down flow path 52 appearing in the flat cross section that is the upper horizontal plane of the divided layer portion 13 is formed in the joint surface 62b of the pre-formed body 62. A groove 82a having a shape corresponding to the horizontal cross-sectional shape of the upper and lower flow paths 52 appearing in the flat cross section that is the lower horizontal plane of the divided layer portion 13 is formed in the joint surface 62a (see FIG. 9).
A groove 83b having a shape corresponding to the horizontal cross-sectional shape of the lower flow path 50b, the upper and lower flow paths 52, and the lower flow path 53b appearing in the flat cross section that is the upper horizontal plane of the dividing layer portion 14 is perforated on the joint surface 63b of the preform 63. A groove portion having a shape corresponding to the horizontal cross-sectional shape of the lower flow path 51b, the upper and lower flow paths 52, and the lower flow path 53b that appears in the flat cross section that is the lower horizontal plane of the divided layer portion 14 is provided on the joint surface 63a of the preform 63. 83a is drilled (see FIG. 10).
A groove portion 84b having a shape corresponding to the horizontal cross-sectional shape of the lower flow path 51b and the upper and lower flow paths 52 appearing in the flat cross section that is the upper horizontal plane of the divided layer portion 15 is formed in the joint surface 64b of the preformed body 64 ( FIG. 11).

  Returning to FIG. 3, in the joining step S <b> 110, the groove portions 80 a and the like drilled in the preforms 60 to 64 using the preforms 60 to 64 in which the groove portions 80 a and the like are drilled in the first processing step S <b> 100. And the preformed bodies 60 to 64 are positioned and fixed so that a part of the cooling water flow path 5 is formed by combining the groove portions 80a and the like formed in the corresponding preformed bodies 60 to 64, respectively. In this state, the preforms 60 to 64 are combined at the corresponding joint surfaces 60a and the like. In addition, in a present Example, it combines so that the preforming bodies 60-64 may become a rectangular parallelepiped shape as a whole (refer FIG. 4).

  Next, in the bonding step S110, the bonding surfaces 60a and the like are bonded as a whole to the preformed bodies 60 to 64 in such a state using solid phase bonding. As this solid phase bonding, a known technique can be adopted, for example, using various pressure welding techniques such as diffusion welding, hot pressure welding, cold pressure welding (room temperature pressure welding), gas pressure welding, and ultrasonic pressure welding. Can do. In particular, in this example, pulse current bonding is preferably used among such known solid-phase bonding.

  Pulse energization bonding is a general term for technologies that apply current (mainly pulsed current) to bonding members and perform bonding with the generated heat, and is suitable for precision bonding of complex-shaped metal parts. It attracts attention as a joining technique that can meet the demand, and a known pulse current joining is also used in this embodiment.

  An example of pulse energization bonding used in this embodiment will be described. First, in this embodiment, a pair of electrode portions that can be electrically conductive with the preforms 60 to 64, and a power supply device that supplies current to the electrode portions. And a known joining device (not shown) comprising a pressurizing device or the like that presses the electrode portion toward the joining surface 60a or the like of the preforms 60 to 64 is used. Then, while pressing the preforms 60 to 64 at a predetermined pressure with a pressurizing device, one or both of a predetermined pulse current and a direct current are passed from the electrode portion to the preforms 60 to 64 and joined. The surfaces 60a and the like are temporarily joined, and then in such a state, heat treatment is performed under a predetermined temperature condition, so that the joint surfaces 60a and the like of the preforms 60 to 64 are joined to obtain one molded body 6.

  In the second processing step S120, the induction heating coil body 10 is cut out of the molded body 6 joined in the joining step S110 based on the shape of the groove 80a and the like. A known processing technique is used as the machining. In that case, it becomes the outer periphery shape of the predetermined induction heating coil body 10 on the basis of the shape of the groove 80a and the like formed inside the molded body 6, that is, the shape of the cooling water flow path 5 of the induction heating coil body 10. So that it is machined.

  As described above, in the method of manufacturing the induction heating coil 1 according to the present embodiment, the preformed bodies 60 to 64 are joined to the plurality of preformed bodies 60 to 64 made of the base material of the induction heating coil body 10 with the joint surfaces 60a and the like. A first processing step S100 for forming a groove portion 80a having a predetermined shape so that the cooling water flow path 5 is formed as a whole by combining, and a preformed body in which the groove portion 80a and the like are formed in the first processing step S100. 60 to 64 are respectively combined at a predetermined bonding surface 60a and the like, and a bonding step S110 is formed by bonding the preforms 60 to 64 by solid phase bonding to form one molded body 6, and the bonding bonded in the bonding step S110. And the second machining step S120 for scraping the induction heating coil body 10 on the basis of the shape of the groove 80a and the like with respect to the body 6, so that the product quality is prevented from being reduced and the induction has an excellent product life. Addition It can be manufactured coil 1.

  That is, according to the manufacturing method of the present embodiment, when the induction heating coil 1 having the cooling water flow path 5 in the hollow interior is manufactured, the continuous portion of the lead conductor portion 3 and the heating conductor portion 4 or the heating conductor portion 4 is used. Even in the configuration in which the bent portion 10a and the like are formed, the lead conductor portion 3, the heating conductor portion 4 and the like can be formed continuously and integrally. Therefore, unlike the induction heating coil manufactured by the conventional manufacturing method, it is not configured to connect a plurality of pipe members having a rectangular cross section by brazing. It is possible to prevent the bonding strength from being reduced and the brazing from being peeled off, thereby improving the product quality and extending the life of the induction heating coil 1.

  In particular, according to the manufacturing method of the present embodiment, when the induction heating coil 1 used for induction hardening of the crankshaft for an engine is manufactured, brazing processing by a conventional worker is not necessary and mechanization is possible. The mechanical strength of the heating coil 1 can be increased to stabilize the quality.

  In addition, in the first processing step S100, when the induction heating coil body 10 is divided into predetermined divided layer portions 11 to 15 by a plurality of parallel horizontal planes 70 to 73, the plane cross sections of the divided layer portions 11 to 15 are obtained. Since the groove 80a having a shape corresponding to the appearing shape is formed in the joint surface 60a of the preforms 60 to 64, the processing to the joint surface 60a is easy, and the joint surface 60a is brought into surface contact. The groove portions 80a and the like can be continued inside the preformed bodies 60 to 64 only by combining the preformed bodies 60 to 64 in a state in which the cooling water flow path 5 can be formed with high accuracy.

  Further, in the first processing step S100, the induction heating coil body 10 is divided into the divided layer portions 11 to 15 having the same number as the preformed bodies 60 to 64 and having the same thickness. The shape appearing in the plane cross section of 11 to 15 can be easily matched with the shape of the groove 80a or the like drilled in the joint surface 60a or the like of the preformed bodies 60 to 64, and the processing accuracy of the cooling water flow path 5 can be increased It can be improved. Further, in such a case, the processing load when the grooves 80a and the like are drilled in the preforms 60 to 64 is reduced by dividing the horizontal plane passing through the bent portions 10a to 10d formed in the induction heating coil body 10. can do.

  In addition, in the joining step S110, the cooling water flow path is obtained by combining the groove portion 80a and the like drilled in the predetermined preformed bodies 60 to 64 and the groove portion 80a and the like drilled in the corresponding preformed bodies 60 to 64. Since the preforms 60 to 64 are positioned so that a part of 5 is formed, the cooling water flow path 5 can be formed with high accuracy and the cutting accuracy of the external shape of the induction heating coil can be improved.

  In addition, as a manufacturing method of the induction heating coil 1 and the structure of the induction heating coil 1, it is not limited to the Example mentioned above, A various change is possible unless it deviates from the objective of this invention.

  That is, in the above-described embodiment, the method of manufacturing one induction heating coil body 10 constituting the induction heating coil 1 has been described. However, the number of induction heating coil bodies 10 or induction heating coils 1 manufactured at one time is as follows. There is no particular limitation. For example, in order to manufacture a plurality of induction heating coil bodies 10 (or a plurality of induction heating coils 1) at a time, the induction heating coil bodies 10 ( Alternatively, a desired number of induction heating coil bodies 10 (or induction heating coils 1) can be formed in the subsequent joining step and the second processing step by drilling grooves 80a and the like corresponding to the induction heating coil 1) at a time. It is possible to manufacture at once.

  In the embodiment described above, one molded body 6 is joined using five preformed bodies 60 to 64, but the number of preformed bodies used is not limited to this, and the induction heating coil to be manufactured. It can change suitably according to the shape of 1. However, the number of preforms is preferably the same as or larger than the number of divided layer portions divided by a predetermined horizontal plane. This is because, by setting the number of preforms as described above, it is possible to reduce the processing burden when the groove is formed in the preform.

  In the above-described embodiment, preforms 60 to 64 having substantially the same thickness (vertical height) are used. The thickness of the preform depends on the shape of the induction heating coil 1 to be manufactured. Thus, it can be appropriately changed for each preform. This is because, depending on the arrangement of the bent portions formed in the induction heating coil 1, it may be preferable to use preforms having different thicknesses.

  Further, in the joining step S110 of the above-described embodiment, various conditions such as joining pressure, joining temperature, and energizing time are appropriately set as pulse energization joining in consideration of the degree of deformation of the preforms 60 to 64 during joining. Adjusted.

  According to the manufacturing method of the embodiment described above, the shape of the induction heating coil 1 to be manufactured is not particularly limited, and the shape of the induction heating coil 1 is appropriately changed according to the outer peripheral shape of the object to be heated 2. It is possible to manufacture an induction heating coil 1 having a wide variety of shapes. For example, the induction heating coil body 10 may have a shape in which a plurality of projecting pieces protruding in a long plate shape are disposed on the outer peripheral surface of the bending portion 40 (upper bending portion 40a and lower bending portion 40b).

  As other shapes, in the induction heating coil 1 of the above-described embodiment, each induction heating coil body 10 is formed in a substantially symmetrical shape in the vertical direction with respect to the horizontal plane passing through the center position in the vertical direction. The shape may be asymmetric in the direction, or the shape in the vertical direction may be different from the shape or number of the bent portions 10a.

  The induction heating coil 1 of the above-described embodiment can be used for induction hardening of a wide range of engine crankshafts as the object to be heated 2. Examples of the object to be heated 2 include gasoline and diesel for automobiles and motorcycles. Examples include general-purpose gasoline engines and general-purpose diesel engines used in various machines such as engines, working machines other than automobiles, and ships.

DESCRIPTION OF SYMBOLS 1 Induction heating coil 2 To-be-heated object 3 Lead conductor part 4 Heating conductor part 5 Cooling water flow path 6 Molded body 10 Induction heating coil body 10a-10d Bending part 11-15 Divided layer part 40 Bending part 41 Vertical connection part 42 Connection part 60 ~ 64 Preliminary molded body 50a etc. Channel 60a etc. Joint surface 80a etc. Groove

Claims (3)

A lead conductor portion that extends in the horizontal direction, a heating conductor portion that is connected to one end of the lead conductor portion and that is formed in a curved shape in the horizontal direction, and cooling water is allowed to flow inside the lead conductor portion and the heating conductor portion. A method for producing an induction heating coil used for induction hardening of an engine crankshaft having a cooling water flow path ,
When the induction heating coil is divided into a plurality of divided layer portions in a plurality of pseudo planes that are parallel to the horizontal direction of the induction heating coil through the bent portion formed in the lead conductor portion and the heating conductor portion. Based on the shape of the cooling water flow path appearing in the plane cross section of the divided layer portion, correspondingly formed groove portions are formed in the joint surfaces of the same number of preformed bodies as the divided layer portion made of the base material of the induction heating coil. A first processing step to be established;
The pre-molded body in which the groove portion is drilled in the first processing step is combined at each joint surface, and a joining step of joining the joint surfaces of the pre-formed body by solid phase joining to form a single molded body,
A second processing step of scraping the induction heating coil based on the shape of the groove, with respect to the molded body joined in the joining step;
A method of manufacturing an induction heating coil used for induction hardening of an engine crankshaft characterized by comprising:   In the joining step, a part of the cooling water flow path is formed by combining the groove portion drilled in a predetermined preform and the groove portion drilled in the corresponding preform body. The method for manufacturing an induction heating coil used for induction hardening of an engine crankshaft according to claim 1, wherein the preform is positioned. An induction heating coil used for induction hardening of a crankshaft for an engine manufactured by the method for manufacturing an induction heating coil according to claim 1 or 2,
An induction heating coil used for induction hardening of a crankshaft for an engine, which is integrally continuous without being brazed at a bent portion.

Images