Induction heating hardening method and induction heating hardening device

Abstract

An induction heating hardening method and an induction heating hardening device are provided that shorten production cycle times. [Solution] An induction heating hardening method for hardening the ends of plate-shaped members using high-frequency induction heating, comprising: placing multiple plate-shaped members in parallel on a jig; using a single hardening coil to induction heat the ends of the multiple plate-shaped members all at once; providing two lines on the jig in which multiple plate-shaped members are placed in parallel in two rows, each with their ends facing each other, sandwiching the single hardening coil; and moving the jig to induction heat the ends of the multiple plate-shaped members row by row at once using the single hardening coil.

Description

[Technical Field]

[0001] The present invention relates to an induction heating hardening method and an induction heating hardening device for hardening the end portion of a plate-shaped member. [Background technology]

[0002] Conventionally, when induction heating a component that requires partial hardening, the component is induction heated and hardened individually one by one using an inductor that matches the shape of the component to be treated and the shape of the area to be hardened (see Patent Documents 1 to 3).

[0003] Patent document 1 describes a method in which an induction action part 21 or 51, 52 is placed opposite one heated area 11 or multiple heated areas 41, 42 defined in an elongated shape on a thin plate article 10 or 40, and high-frequency current is passed through this induction action part, thereby simultaneously inductively heating the entire area of ​​the one or multiple heated areas (see abstract, claims 1 and 2; Figures 1 and 4).

[0004] Patent Document 2 describes a method for induction hardening a stepped member 1, such as a pole parking pole, which has a material region M and a machining region N adjacent to this material region M via a step portion 6, and which uses the stepped member as the hardening target.The method involves a pair of electrode contacts 7, 8 being brought into contact with a portion of the material region M, which is in the vicinity of the step portion 6, and applying electricity directly to the machining region N to heat the machining region N, and then cooling the machining region N, which has been heated to the required hardening temperature, with a quenching coolant 9, thereby forming a quench-hardened layer S in the machining region (abstract, claims 1 and 3; see Figures 1 and 2).

[0005] Patent document 3 describes an induction heating hardening method for a long material 10 in which a first side portion 11 and a second side portion 12 are adjacent to each other at a corner 13, a recess is provided in the first side portion 11 away from the corner 13, and the first and second side portions 11, 12 and the recess 14 are continuous in the longitudinal direction, in order to induction heat the first side portion 11 and the recess 14, using a heating coil 21 for the long material 10 in which a wide conductor 24 facing the first side 11 and a narrow conductor 23 facing the recess 14 and protruding toward the recess 14 from the wide conductor 24 (abstract, see claim 1; Figure 1).

[0006] On the other hand, in order to perform induction heating quenching efficiently, multiple workpieces are sometimes quenched simultaneously (see Patent Documents 4 and 5).

[0007] Patent Document 4 describes a method in which a plurality of base metals 8, which are the workpieces, are stacked, electrodes 4 and 5 are pressed against the top and bottom surfaces of the stack, the outer periphery of the base metals 8 is covered in a case in a substantially sealed state, an inert gas is supplied into the case, and then a high-frequency current is supplied between the electrodes to harden the base metals 8 (see abstract, claim 1, and FIG. 1).

[0008] Patent document 5 describes a method in which a plurality of workpieces 10 (13, 14) are temporarily assembled into a workpiece assembly 13+14 by interconnecting them with conductive joints 15 so that the respective hardening target regions 11 are connected in series endlessly to form a closed circuit and the positional relationship between each body is fixed, and an inductor 17 that generates a magnetic flux in the same direction as the axis of the assembly is placed outside the assembly, and high-frequency current is applied to the inductor 17, thereby generating an induced current that circulates around the closed circuit in a manner that increases the coupling coefficient, which is an indicator of the degree of coupling between the inductor and the workpiece, and thereby simultaneously hardening the plurality of hardening target regions 11, 11 (abstract, claim 1; see Figure 1). Furthermore, Patent Document 5 states, "In all of the conventional methods for quenching thin steel sheet formed products described above, the workpiece is single in nature. For this reason, when processing a large number of items, processing each item one by one takes time, and simply increasing the number of items to be processed and performing parallel or concurrent processing results in correspondingly higher equipment costs." (Paragraph

[0006] ) [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-054225 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-105301 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013182840 [Patent Document 4] Japanese Patent Application Publication No. 7-216457 [Patent Document 5] Japanese Patent Application Laid-Open No. 2008-45183 Summary of the Invention [Problem to be solved by the invention]

[0010] The quenching methods described in Patent Documents 1 to 3 are methods in which workpieces are quenched individually, which means that production efficiency cannot be improved and they are not suitable for mass production. Patent Documents 4 and 5 describe quenching a plurality of workpieces at once. However, the quenching method described in Patent Document 4 is applicable to workpieces such as base metals having a certain thickness that can be pressure welded, and is not generally applicable to plate-like members having various shapes. In addition, since a pretreatment step of sealing the treatment atmosphere and replacing it with an inert gas is required, it is difficult to improve production efficiency. The quenching process described in Patent Document 5 requires a complex pre-processing step of assembling a group of workpieces in such a way that the multiple workpieces are connected in series in an endless manner to form a closed circuit, and the positional relationship between each workpiece is fixed. Therefore, this process also lacks versatility, making it difficult to improve production efficiency. Furthermore, Patent Document 5 describes, as a conventional technique, parallel processing as a method for quenching a large number of thin steel sheet formed products (plate-shaped members), but does not disclose a specific processing method.

[0011] In view of the above problems, an object of the present invention is to provide an induction heating hardening method and an induction heating hardening device that can efficiently perform partial hardening of a plurality of plate-shaped members. [Means for solving the problem]

[0012] In order to solve the above problems, the present invention employs the following means. (1) An induction heating hardening method for hardening the ends of a plate-shaped member by high-frequency induction heating, comprising: placing a plurality of plate-shaped members in parallel on a jig; and inductively heating the ends of the plurality of plate-shaped members at once with a single hardening coil; two lines are provided on the jig in which a plurality of plate-shaped members are placed in parallel in two rows with their ends facing each other across the single hardening coil, and the jig is moved to induction heat the ends of the plurality of plate-shaped members row by row at once with the single hardening coil; An induction heating hardening method, wherein a distance is secured between the hardening position on the first line of the jig and the hardening position on the second line so that the induction magnetic field generated during hardening on one line of the single hardening coil does not interfere with multiple plate-shaped members on the other line.

[0013] (2) one hardened coil; a jig having two lines on which a plurality of plate-shaped members are placed in parallel with each other so that their ends face each other across the hardening coil; a moving mechanism that moves the jig between a hardening position where ends of a plurality of plate-shaped members on a first line are hardened by the hardening coil, and a hardening position where ends of another plurality of plate-shaped members on a second line are hardened by the hardening coil; a loading / unloading mechanism for unloading the plurality of induction-hardened plate-shaped members from each of the lines, the attachment / detachment mechanism includes a mechanism for carrying out the plurality of quenched plate-shaped members on the second line while ends of the plurality of plate-shaped members on the first line are at the quenching position, and placing a plurality of plate-shaped members to be new quenched on the second line in parallel so that their ends face ends of the plurality of plate-shaped members on the first line, and a mechanism for carrying out the plurality of quenched plate-shaped members on the first line while ends of the plurality of plate-shaped members on the second line are at the quenching position, and placing a plurality of plate-shaped members to be new quenched on the first line in parallel so that their ends face ends of the plurality of plate-shaped members on the second line, An induction heating hardening device in which a distance is ensured between the hardening position on the first line of the jig and the hardening position on the second line so that the induction magnetic field generated during hardening on one line of the single hardening coil does not interfere with multiple plate-shaped members on the other line. [Effects of the Invention]

[0014] According to the present invention, partial quenching of multiple plate-shaped members can be performed without requiring any special pre-processing, thereby providing an induction heating quenching method and induction heating quenching device with improved production efficiency. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a schematic plan view of an induction heating hardening device according to an embodiment of the present invention; [Figure 2] FIG. 1 is a schematic plan view showing a quenching position and a detachment position of an induction heating quenching device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] (Induction heating hardening method) An induction heating hardening method according to an embodiment of the present invention (hereinafter referred to as "this embodiment") is an induction heating hardening method for hardening the ends of a plate-shaped member by high-frequency induction heating, in which multiple plate-shaped members are placed in parallel on a jig and the ends of the multiple plate-shaped members are induction heated at once using a single hardening coil. In this way, induction heating and hardening can be performed at one time using one hardening coil, so no special pre-processing is required, thereby improving production efficiency.

[0017] More specifically, the induction heating hardening method according to this embodiment is a method in which a plurality of plate-shaped members are placed in two parallel rows on a jig with their ends facing each other across the single hardening coil, and the jig is moved so that the ends of the plurality of plate-shaped members are induction heated row by row at once with the single hardening coil. In this way, a single hardening coil is used to induction heat a plurality of plate-like members placed in two rows at once, row by row, further improving production efficiency.

[0018] The quenching method according to this embodiment will be specifically described below with reference to FIG. (1) On two lines (hereinafter referred to as the "first line" and the "second line") provided on the jig, a plurality of plate-shaped members are placed in two parallel rows with the ends, which are the areas to be hardened, facing each other. (2) One hardening coil and the jig are moved relative to each other, and the ends of multiple plate-shaped members on a first line (shown as "line A" in the figure; the same applies below) are induction heated with the single hardening coil at once, and then cooled to complete the hardening (cooling jacket not shown). Meanwhile, multiple plate-shaped members placed on a second line (shown as "line B" in the figure; the same applies below) are not affected by the induction magnetic field generated when the hardening coil is induction heated on the first line. (3) Next, the single hardening coil and the jig are moved relative to each other, and the hardening coil simultaneously induction heats the ends of the multiple plate-shaped members on the second line, followed by cooling to complete the hardening. Meanwhile, the multiple plate-shaped members that have been hardened on the first line are removed, and multiple new plate-shaped members to be hardened are placed on the first line. The newly placed multiple plate-shaped members are also not affected by the induction magnetic field generated by the hardening coil during induction heating on the second line. (4) Again, the hardening coil and the jig are moved relative to each other, so that the ends of the plurality of plate-shaped members on the first line are induction-heated at once by the hardening coil, and then cooled to complete the hardening. Meanwhile, the plurality of plate-shaped members that have been hardened on the second line are carried out, and the plurality of plate-shaped members to be newly hardened are placed on the second line. (5) The steps (3) and (4) are repeated as many times as desired, and production is stopped when the desired number of hardened products has been obtained.

[0019] (Plate-shaped member) The material of the plate-shaped member is not limited as long as it is hardenable, but steel members are preferred, and the method and apparatus of this embodiment can be used to harden, for example, S48C (C: 0.45 to 0.51, Si: 0.15 to 0.35, Mn: 0.60 to 0.90, P: 0.030 or less, S: 0.035 or less) carbon steel for mechanical structures.

[0020] (Induction heating hardening equipment) FIG. 1 shows a schematic plan view of an induction heating hardening device according to this embodiment. This device includes a hardening coil, a jig with two lines on which multiple plate-shaped members are placed in parallel with their ends facing each other, sandwiching the hardening coil, a moving mechanism (not shown) that moves the jig between a hardening position on the first line of the jig where the ends of multiple plate-shaped members are hardened by the hardening coil, and a hardening position on the second line where the ends of another multiple plate-shaped members are hardened by the hardening coil, and a loading / unloading mechanism (not shown) that transports the multiple plate-shaped members that have been hardened by the hardening coil from each of the lines.

[0021] The moving mechanism and the detaching mechanism will be described with reference to FIG. The left diagram in Figure 2 shows a state in which the jig and one hardening coil are moved relative to each other by a moving mechanism (not shown), and the ends of multiple plate-shaped members placed on the first line are in a position to be hardened by the one hardening coil. While in this state, if multiple plate-shaped components that have been hardened are placed on the second line, they are removed by a mounting / dismounting mechanism (not shown) and new components to be hardened are placed on the second line. The right diagram in Figure 2 shows a state in which the jig and one hardening coil are moved relative to each other by a moving mechanism (not shown), and the ends of multiple plate-shaped members placed on the second line are in a position to be hardened by the one hardening coil. While in this state, if multiple plate-shaped members that have been hardened are placed on the first line, they are removed by a mounting / dismounting mechanism (not shown) and new members to be hardened are placed on the first line.

[0022] That is, the attachment / detachment mechanism has a mechanism for transporting the quenched plate members on the second line while the ends of the plate members on the first line are at the quenching position, and placing the new plate members to be quenched on the second line in parallel with their ends facing each other, and a mechanism for transporting the quenched plate members on the first line while the ends of the plate members on the second line are at the quenching position, and placing the new plate members to be quenched on the first line in parallel with their ends facing each other.

[0023] The hardening coil is usually configured to be connected to a high-frequency power source, a cooling device, etc. Therefore, the moving mechanism is preferably a mechanism that fixes one hardening coil and moves a jig, but it may also be a mechanism that fixes the jig and moves one hardening coil. Furthermore, the hardening coil is not particularly limited as long as it has a shape that allows a plurality of plate-shaped members to be placed in parallel on a jig and the ends of the plurality of plate-shaped members to be induction-heated at once with one hardening coil.

[0024] In addition, in order to improve the uniformity of the hardening, it is preferable to ensure a distance between the hardening positions on the first line and the second line so that the induced magnetic field generated during hardening on one line of the single hardening coil does not interfere with the multiple plate-shaped members on the other line. [Industrial Applicability]

[0025] The induction heating hardening method and induction heating hardening device according to the present invention can significantly improve productivity, and can therefore be effectively used in the mass production of steel parts.

Claims

1. An induction heating hardening method for hardening the ends of a plate-shaped member by high-frequency induction heating, comprising: placing a plurality of plate-shaped members in parallel on a jig; and inductively heating the ends of the plurality of plate-shaped members at once with a single hardening coil; two lines are provided on the jig in which a plurality of plate-like members are placed in parallel in two rows with their ends facing each other across the single hardening coil, and the jig is moved to induction heat the ends of the plurality of plate-like members row by row at once with the single hardening coil; An induction heating hardening method in which a distance is ensured between the hardening position on the first line of the jig and the hardening position on the second line so that the induction magnetic field generated during hardening on one line of the single hardening coil does not interfere with multiple plate-shaped members on the other line.

2. one hardened coil; a jig having two lines on which a plurality of plate-like members are placed in parallel with each other so that their ends face each other across the hardening coil; a moving mechanism that moves the jig between a hardening position where ends of a plurality of plate-shaped members on a first line are hardened by the hardening coil, and a hardening position where ends of another plurality of plate-shaped members on a second line are hardened by the hardening coil; a loading / unloading mechanism for unloading the plurality of induction-hardened plate-shaped members from each of the lines, the attachment / detachment mechanism includes a mechanism for carrying out the quenched plate-shaped members on the second line while ends of the plate-shaped members on the first line are at the quenching position, and placing the plate-shaped members to be new quenched on the second line in parallel so that their ends face the ends of the plate-shaped members on the first line, and a mechanism for carrying out the quenched plate-shaped members on the first line while ends of the plate-shaped members on the second line are at the quenching position, and placing the plate-shaped members to be new quenched on the first line in parallel so that their ends face the ends of the plate-shaped members on the second line, An induction heating hardening device in which a distance is ensured between the hardening position on the first line of the jig and the hardening position on the second line so that the induction magnetic field generated during hardening on one line of the single hardening coil does not interfere with multiple plate-shaped members on the other line.

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