JP3326450B2 - Induction heating equipment for non-linear rod-shaped members - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to induction heating for induction heating and quenching a non-linear rod-like member such as a torsion bar for a stabilizer of an automobile or brazing a curved tube or the like. The present invention relates to a quenching device or an induction heating device.

[0002]

2. Description of the Related Art Conventionally, as a spring material such as a torsion bar, a bar steel member or a hardened steel pipe whose surface is hardened by induction heating to improve fatigue strength is used. For example, a member which is bent in a non-linear manner with a two-dimensional or three-dimensional angle or curve, such as a torsion bar for a stabilizer of an automobile, conventionally has a predetermined shape after heat-treating a steel bar or a steel pipe to a predetermined hardness in a linear state. It was manufactured by bending into a non-linear shape. However, when the quenching hardness is high, bending after quenching becomes difficult, especially when the member is not a solid material such as a steel bar but a hollow material such as a steel pipe, it is difficult to bend a hard material. . Therefore, there is a method of bending the quenched material by warm working, or by heating the bent part and re-quenching after bending, but such a method requires more man-hours for members with complicated shapes and costs. There was a problem that the cost was high.

On the other hand, according to a method in which a steel bar or a steel pipe is bent in an annealed state and then quenched by induction heating, bending can be easily performed and a complicated shape can be processed, and the number of steps is reduced. Cost can be reduced.
Conventionally, in the quenching of a member bent into such a non-linear shape, a method in which a member to be processed is sequentially passed through a circular induction coil from an end portion and quenched while locally performing induction heating to quench the entire member. Was taken.

[0004]

However, in the above-described conventional induction heating method, it is difficult to pass a complicated curved member having corners and the like through an induction coil.
In addition, there is a problem that it takes time to quench one member, which results in low mass productivity and high cost. It has also been desired to improve a cooling means capable of uniformly quenching and cooling a member having a complicated shape such as a torsion bar.

Accordingly, the present invention solves the above-mentioned problems, and can improve the quality by inducing the entire quenched portion at one time even with a member having a complicated shape, and uniformly cooling and quenching the entire quenched portion. It is another object of the present invention to provide an induction heating apparatus for a non-linear rod-shaped member which is easy to mass-produce with reduced cost. Further, the induction heating apparatus can be used not only for quenching but also for heating when brazing a non-linear member.

[0006]

Means for Solving the Problems] To achieve the above object, the induction heat treatment apparatus of the non-linear rod-like member of the present invention, the quenching apparatus for induction hardening the rod member of the non-linear, the hardened rod-like Has a curve similar to the linear curve of the member
Conductors are provided in at least four places on the outer periphery of the rod-shaped member.
It is arranged so as to be wound, and is flat along the curved shape of the rod-shaped member.
Induction heating means provided with an induction heating coil extended in a row, and cooling means for simultaneously liquid cooling the entire quenched portion of the quenched rod-shaped member heated to the quenching temperature by the induction heating means. It is characterized by the following.

That is, in the induction heating apparatus of the present invention, the induction heating coil having the conductor having a curve similar to the curve of the member to be heated is extended along the non-linear line direction of the member to be heated. Even with a heated member having a complicated shape that is bent two-dimensionally or three-dimensionally, the entire length of the heating portion is heated at a time. Further, since at least four or more coils are disposed around the outer periphery of the heated member, the outer periphery of the heated member is uniformly heated. Therefore, even for a heated member having a complicated shape that is bent two-dimensionally or three-dimensionally, the entire length can be heated at a time without heating each part. Therefore, man-hours can be reduced, mass production can be performed, and cost can be reduced. . Here, the non-linear rod shape includes a rod material, a pipe material, a plate material, and the like that are bent two-dimensionally or three-dimensionally with an angle, or bent with a curve such as an arc. In addition,
If the induction heating coil is extended in the direction of the line of the non-linear rod parallel to the outer periphery thereof, the length of the member can be uniformly heated. If it changes, the member can be heated by giving a temperature difference. Further, the induction heating treatment apparatus of the present invention can be widely applied not only to heat treatment such as quenching, but also to heating at the time of brazing a non-linear rod-shaped member.

Further, the induction heating and quenching apparatus for a non-linear rod-shaped member of the present invention has a curve similar to a linear curve of a rod-shaped member to be quenched.
Conductors having at least four locations on the outer periphery of the rod-shaped member
And is arranged along the curved shape of the rod-shaped member.
And a cooling means for simultaneously liquid cooling the entire quenched portion of the quenched rod-shaped member heated to the quenching temperature by the induction heating means. It is characterized by having.

That is, according to the induction heating and quenching apparatus of the present invention, the induction heating coil of the induction heating means extends in the same manner as described above along the shape of the member to be quenched and parallel to its line direction. Since four or more coils are arranged around the outer periphery of the member to be quenched, even a non-linear member having a complicated shape that is bent two-dimensionally or three-dimensionally, the entire periphery of the quenched portion during quenching heating.・ The entire length is heated at once. Therefore, even a hardened member having a complicated shape that is bent two-dimensionally or three-dimensionally, such as a torsion bar, can be heated and quenched at a time without quenching part by part, thereby reducing man-hours and enabling mass production. Cost can be reduced.

Further, since the cooling means for simultaneously liquid cooling the entire quenched portion of the member to be quenched is provided, the entire member heated to the quenching temperature is rapidly cooled at the same time, and uniform quench hardness can be obtained.

When the surfaces of the two boxes are overlapped with each other, the cooling means is provided on a quenching portion of the quenched rod-shaped member on the mating surface.
A curve that covers the entire length and is substantially similar to the curve of the outer shape of the rod-shaped member
A plurality of cooling boxes having a cavity formed therein , wherein a plurality of injection holes for injecting cooling liquid are provided on the inner wall surface of the concave portion on the entire outer circumference of the quenched rod-shaped member inserted into the cavity. It is desirable to do.

That is, the cavity into which the member to be quenched is inserted is 2
Since two cooling boxes are formed so as to be formed when they are stacked, the member to be quenched can be easily inserted into the cooling means, and rapid quenching after quenching and heating is possible. Also, since the cavity formed when the two cooling boxes are stacked is similar to the outer shape of the member to be quenched, when the member to be quenched is inserted into this cavity, the member to be quenched and the coolant are removed. The distance from the inner wall of the cavity provided with the injection port becomes substantially uniform. Therefore,
When the member to be quenched heated to the quenching temperature by the induction heating means is inserted into the cavity, and the coolant is injected from the plurality of injection ports on the inner wall of the cavity, the entire length and the entire surface of the member to be quenched become even at once. Cools quickly and uniformly. This makes it possible to obtain uniform heat treatment hardness and structure without uneven quenching throughout the quenched member.

The induction heating and quenching apparatus for a non-linear rod-shaped member of the present invention is suitable for quenching a torsion bar of a complicated curved rod or tube.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the drawings. FIG. 1 is a perspective view of a heating means of the induction heating and quenching device for a non-linear rod-shaped member of the present invention, FIG. 2 is a sectional view taken along line XX of FIG. 1, and FIG. is there.

As shown in these figures, the quenched member 1 of the present embodiment is a torsion bar formed of a three-dimensionally bent steel pipe. Induction heating coil 10 of heating means 2
Consists of an upper coil 11 and a lower coil 21 of conductors processed into a curve similar to the curve in the linear direction of the member 1 to be quenched, and is disposed parallel to the line direction along the curved shape of the member 1 to be quenched. You. The upper coil 11 and the lower coil 21 are long enough to cover the entire length of the quenched portion of the quenched member 1, and an example is shown in FIG. 1 in a shape that allows easy insertion and removal of the quenched member 1 in the Y direction. Have been. Each of the coils 11 and 12 is disposed such that four coil cross sections are equally spaced on the outer periphery of the member 1 to be quenched as shown in the cross-sectional view of FIG. When it is desired to change the quenching hardness by locally changing the heating temperature of the member to be quenched, the upper and lower coils 11a, 11b, 21a, 2
1b may be disposed not parallel to the bent shape of the member 1 to be quenched, and may not be equidistant on the outer periphery of the member 1 to be quenched.

The upper and lower coils 11, 21 are connected to form the following circuit. That is, as shown by the arrow in FIG. 1, the high-frequency current introduced from the terminal 12 passes through the upper right coil 11a and the upper left coil 11b from the left in the figure.
And the lower right coil 21a via the connection coil 13
And flows through the lower right coil 21a from the left side of the figure to the terminal 14 through the lower right coil 21a. Thus, an induction coil circuit in which current flows in the same direction is formed in the upper coil 11 and the lower coil 21. These coils are molded from a hollow copper tube and water-cooled like ordinary induction coils.

The cooling means 3 shown in FIG. 3 comprises a hollow upper tank (cooling box) 31 and a lower tank (cooling box) 41.
The upper tank 31 and the lower tank 41 are used by being vertically overlapped, and the upper concave portion 32 and the lower concave portion 42 are provided on respective mating surfaces.
Is provided. When the upper concave portion 32 and the lower concave portion 42 are combined, a space 30 similar to the curved shape of the quenched member 1 into which the quenched member 1 is inserted is formed. Numerous coolant injection holes 32a and 42a are provided inside the upper recess 32 and the lower recess 42, respectively.
The cooling liquid injected into the upper tank 31 and the lower tank 41 is ejected from 3 and 43 to rapidly cool the quenched member 1 (not shown) inserted into the space 30.

Hereinafter, the operation of the induction heating and quenching apparatus of the present invention having the above-described structure will be described. When the member 1 to be quenched is inserted into the induction heating coil 10 as shown in FIGS. 1 and 2 and a high-frequency current is applied to the induction heating coil 10, a magnetic flux as shown in FIG. Heated. Since the four induction heating coils are arranged at an equal distance around the outer periphery of the quenched member 1 and in parallel to the line direction, the quenched member 1 is heated to a uniform temperature in the entire length direction. Is done.

After the quenched member 1 is heated to a predetermined quenching temperature by the heating means 2 and held for a predetermined time, the induction heating coil 1
0 and is inserted into the cavity 30 of the cooling means 3. And after combining the upper tank 31 and the lower tank 41,
The cooling liquid is injected from the injection pipes 33 and 43, and is cooled by jetting the cooling liquid from the injection holes 32a and 42a of the upper recess 32 and the lower recess 42. As a result, the entire periphery of the quenched member 1 is uniformly cooled over the entire length of the quenched portion, and quenched to a uniform hardness.

[0020]

Example 1 The following test was conducted by using the induction heating and quenching apparatus having the above configuration. Heating conditions: 1000 ° C x 30 sec water cooling Additional power supply: MG6kHz

The torsion bar 10 quenched under the above conditions
The book was cut at intervals of 100 mm to obtain a cross-sectional sample, and the hardness distribution of the quenched layer was measured by a Vickers hardness meter, and the depth of the quenched layer was measured by etching. As a result, the depth of the quenched layer was within 6 mm ± 1.0 mm (within JIS standard), and the hardness was within Hv700 ± 30.

[0022]

Example 2 Member to be quenched: Member name: torsion bar Material: STKM13A Dimensions: Steel tube with outer diameter 31 mmφ, wall thickness 5 mm Length 1100 mm Shape Details omitted (same shape as in Example 1) Heating condition: 1100 ° C. × 20 sec water cooling Additional power supply: MG6kHz

The torsion bar 10 quenched under the above conditions
The book was cut at intervals of 100 mm in the same manner as in Example 1 to obtain a cross-sectional sample, and the hardness and depth of the quenched layer were similarly measured by Vickers hardness meter and etching. The result is quenched to the entire inner diameter of the sample, and its hardness is Hv700 ±
It was within 30.

As described above, according to the non-linear member induction heating and quenching apparatus of the embodiment of the present invention, the induction heating coil is extended along the curved linear direction of the member to be quenched.
In addition, since at least four or more coils are disposed around the outer periphery of the member to be heated, the entire length of the outer periphery of the heating portion of the member to be quenched can be uniformly heated at a time. Therefore, even a hardened member having a complicated shape that is bent two-dimensionally or three-dimensionally, such as a torsion bar, can be heated all at once without heating part by part, so that man-hours can be reduced, mass production becomes possible, and cost is reduced. it can.

Further, the induction heating and quenching apparatus of the present invention is provided with cooling means for simultaneously liquid cooling the entire quenched portion of the member to be quenched, and the cooling means is a hollow portion formed by combining two cooling boxes. Since the member to be quenched is inserted and cooled, rapid cooling can be performed after heating. In addition, this hollow portion covers the entire quenched portion of the quenched member substantially similar to the outer shape of the quenched member,
A cooling liquid injection port is provided on the inner wall. Thus, when the quenched member heated to the quenching temperature is inserted into this hollow portion and the cooling liquid is injected from the injection port, the entire length and the entire surface of the quenched member are rapidly and uniformly cooled at once, and the quenched member is cooled. A uniform heat treatment hardness and structure can be obtained throughout.

The induction heat treatment apparatus of the present invention heat-treats all non-linear rod members such as rods, pipes, and plates that are bent two-dimensionally or three-dimensionally at an angle, or bent at a curve such as an arc. Can be. If the induction heating coil is arranged not parallel to the line direction of the rod to be processed but at a different distance from the outer periphery of the rod, the member to be processed can be heated with a partial temperature difference. Further, the induction heating treatment apparatus of the present invention can be widely applied not only to heat treatment such as quenching, but also to heating at the time of brazing a non-linear rod-shaped member.

[0027]

As described above, according to the induction heating apparatus for a non-linear rod-shaped member of the present invention, the entire non-linear rod-shaped member processed two-dimensionally or three-dimensionally is heated simultaneously. Therefore, the heat treatment can be performed in a shorter time as compared with the conventional heat treatment method using partial heating, and mass production is easy and cost can be reduced. In addition, since the induction heating and quenching apparatus for a non-linear rod-shaped member of the present invention is provided with a cooling means capable of cooling the entire non-linear rod-shaped quenched member heated by induction at a time, the quenching of a complicated shape is performed. Even with a member, uniform hardening hardness and structure can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of an induction heating and quenching device for a non-linear rod-shaped member according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a perspective view of a cooling means of the induction heating and quenching device for the non-linear rod-shaped member according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Torsion bar (hardened member) 2 Induction heating means 3 Cooling means 10 Induction heating coil 11 Upper heating coil 11a Upper right heating coil 11b Upper left heating coil 12 Terminal 13 Connecting coil 14 Terminal 21 Lower heating coil 21a Lower right heating coil 21b Lower left heating coil 30 Cavity part 31 Upper tank (cooling box) 32 Upper concave part 32a Injection port 33 Injection pipe 41 Lower tank (cooling box) 42 Lower concave part 42a Injection port 43 Injection pipe

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sadahiro Terada 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Yoichi Taniguchi 5-33-8 Shiba, Minato-ku, Tokyo No. Mitsubishi Motors Corporation (72) Inventor Kenji Kato 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation (56) References JP-A-59-126715 (JP, A) Kaihei 2-138892 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 6/36 H05B 6/10 B23K 1/002 C21D 1/10 C21D 1/42 H05B 6/02

Claims (4)

(57) [Claims] 1. A heating apparatus for induction heating a non-linear rod-like member, wherein the heat-treating apparatus is similar to a linear curve of a rod-like member to be heated.
Is the conductor having the curve of at least 4 on the outer periphery of the rod-shaped member?
A curved shape of the bar-shaped member
An induction heating treatment device for a non-linear rod-shaped member, comprising: an induction heating coil extending in parallel along a shape . 2. A hardening apparatus for inductively heating quenching a rod member of the non-linear phase and the line direction of the curve of the hardened rod member
A conductor having a similar curve is at least 4
The rod-shaped member is disposed so as to surround at least
An induction heating means provided with an induction heating coil extending in parallel along the shape, and a cooling means for simultaneously liquid cooling the entire quenched portion of the quenched rod-shaped member heated to the quenching temperature by the induction heating means. An induction heating and quenching apparatus for a non-linear rod-shaped member, comprising: 3. The quenching means for quenching the quenched rod-shaped member on the mating surface when the surfaces of the two boxes are overlapped.
A curve which covers the entire length and is substantially similar to the curve of the outer shape of the rod-shaped member
And a plurality of injection holes for injecting cooling liquid over the entire outer circumference of the quenched rod-shaped member inserted into the hollow portion on the inner wall surface of the concave portion. The induction hardening apparatus for a non-linear rod-shaped member according to claim 2, characterized in that: 4. The induction heating and quenching apparatus for a non-linear rod-shaped member according to claim 2, wherein the non-linear rod-shaped member is a torsion bar of a rod or a tube.