JPH10324911A - Induction hardening coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an induction hardening coil for heating the inner surfaces of grooves in a bottomed cylindrical work with plural grooves formed on the inner surface. SOLUTION: This induction hardening coil is provided with plural groove heating conductive parts 100A, 100B, 100C faced to the inner surfaces of the grooves in the bottomed cylindrical work with plural grooves formed on the inner surface, plural connecting conductive parts 200A, 200B mutually connecting adjacent groove heating conductive parts with each other and one pair of electric supplying conductive parts 300A, 300B connected with the groove heating conductive parts 100a, 100B, 100C. The connecting conductive parts 200A, 200B are provided with one pair of first connectors 210A, 210B connected with the parts between connecting parts of the adjacent groove heating conductive parts 100A, 100B, 100C and second connectors 220A, 220B connected with the first connectors and positioned at both sides of the line connecting the center point of the bottomed cylinder work with the center part of the groove. The first connectors 210A, 210B are extendedly set in the direction almost right angle to the groove heating conductive parts 100A, 100B, 100C and in the adjacent first connectors 210A, 210B, the current in the reverse direction is flowed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction hardening coil for heating the inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on the inner surface.

[0002]

2. Description of the Related Art As a bottomed cylindrical work having a plurality of grooves formed on an inner surface, there is a tripod housing member W used for a constant velocity joint. As an induction hardening coil for performing induction hardening on the inner surface of the tripod housing member W shown in FIG. 6, there is one shown in FIG.

First, the induction hardened coils shown in FIG. 4 are arranged facing each other at substantially constant intervals along the inner surfaces of the tripod housing member W. However, in this induction hardened coil, although the thickened portion W3 is subjected to induction hardening to form a hardened layer (shown by oblique lines in FIG. 4), the left and right side surfaces W11 and the thin wall of the groove W1 are formed. There is a problem that induction hardening is not performed on the portion W12 and a hardened layer is not formed. In particular, both side surfaces W of the groove W1
There is a problem in that a corner portion at a boundary between the first portion 11 and the thick portion W3 is heated. The cause is a characteristic in high-frequency heating that the convex portion is easily heated, but the concave portion is not easily heated. Further, both sides W of the groove W1 are formed by the induction hardening coil.
In order to form a hardened layer by applying induction hardening also to the thin portion 11 and the thin portion W12, it is conceivable to apply a larger current. However, in this case, the thick portion W3 is overheated, and the inner surface of the tripod housing member is formed. Deformation due to thermal imbalance may occur.

Therefore, an induction hardening coil shown in FIG. 5 can be considered. In such an induction hardening coil, a heating conductor corresponding to the thick portion W3 is provided separately from the thick portion W3. In this state, when a current capable of performing a predetermined induction hardening on the thick portion W3 is passed through the induction hardening coil, both side surfaces W11 of the groove W1 and the thin portion W12 are overheated, and particularly, the thin portion W12 has a bump. There is a risk of quenching. In addition, overheating of the corner cannot be avoided.

To solve such a problem, Japanese Patent Publication No. Sho 63
An induction hardening coil as described in U.S. Pat. No. 4,428,39 has been devised. Such an induction hardening coil,
As set forth in the claims, "in the induction hardening coil for moving quenching of a cylindrical internal surface having an unequal thickness portion, the heating conductor corresponding to the thick portion of the cylindrical internal surface may be provided. A pair of rising portions extending along the axial direction of the cylindrical body and extending in parallel with the thickest portion, and these rising portions are arranged in parallel and close to each other, The arrangement is such that currents in opposite directions flow through the arranged rising portions.

As a result, the electromagnetic action is canceled in the rising portion facing the (most) thick portion, so that heating of the thick portion by the rising portion is suppressed, and overheating of the thick portion is prevented. .

[0007]

However, the induction hardening coil described in Japanese Patent Publication No. 63-42839 has the following problems. That is, overheating of the corner portion of the tripod housing member W cannot be avoided.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an induction hardening coil which can perform appropriate high frequency heating without overheating the corners.

[0009]

An induction hardening coil according to the present invention is an induction hardening coil for heating an inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on an inner surface thereof, wherein the groove is heated. A plurality of groove heating conductors facing the inner surface of the groove heating conductor, a plurality of connection conductors interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair of power supply connected to the groove heating conductor. And a pair of first connection conductors connected between connection portions of adjacent groove heating conductor portions, and a second connection conductor connecting the first connection conductors to each other. The connecting portion is located on both sides of a line connecting a center point of the bottomed cylindrical work and a center portion of the groove, and the first
The connection conductor extends in a direction substantially orthogonal to the groove heating conductor, and is configured such that a current in the opposite direction flows through the adjacent first connection conductor.

According to another aspect of the present invention, there is provided an induction hardening coil for heating an inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on an inner surface thereof. A plurality of groove heating conductors facing the inner surface of the groove heating conductor, a plurality of connection conductors interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair of power supply connected to the groove heating conductor. And a pair of first connection conductors connected between connection portions of adjacent groove heating conductor portions, and a second connection conductor connecting the first connection conductors to each other. Wherein the connection portion is located on a line connecting a center point of the bottomed cylindrical work and a center portion of the groove, and the first connection conductor is substantially orthogonal to the groove heating conductor portion. So that a current in the opposite direction flows through the adjacent first connection conductor. It has been.

[0011]

FIG. 1 is a schematic perspective view of an induction hardened coil according to a first embodiment of the present invention, and FIG. 2 is a perspective view of the induction hardened coil according to the first embodiment of the present invention. FIG. 3 is a schematic bottom view showing the relationship between a bottomed cylindrical work and a tripod housing member. FIG. 3 is a high-frequency hardening coil according to a second embodiment of the present invention and a bottomed tubular work as a tripod housing. It is a schematic bottom view which shows the relationship with a member.

The induction hardened coil according to the first embodiment of the present invention heats the inner surface of the groove W1 of the tripod housing member W which is a bottomed cylindrical work having three grooves W1 formed on the inner surface. Induction hardening coil, three groove heating conductor portions 100A, 100 facing the inner surface of groove W1
B, 100C and the groove heating conductors 100A, 100B
Conductor portion 200A for connecting the groove heating conductor portion 1
A connection conductor portion 200B for connecting 00A and 100C, and two power supply conductor portions 300A and 300B connected to the groove heating conductor portions 100B and 100C are provided.

Each of the conductors constituting the induction hardened coil has a conductive property capable of circulating a cooling liquid therein in order to prevent itself from being overheated when the tripod housing member W is heated. It consists of a pipe having.

The three groove heating conductors 100A, 100B,
100C is formed in a substantially C-shape in plan view along the shape of the groove W1. That is, each heating conductor 100A,
100B and 100C are left and right side surfaces W11 of the groove W1.
And the thin portion W12 therebetween at predetermined intervals. These three groove heating conductor portions 100A, 100B, 100C are set so as to be arranged on the same plane.

The three groove heating conductors 100A, 10A
The grooves 0B and 100C are arranged at an angle of 120 ° to each other because the groove W1 is formed every 120 °. The three groove heating conductors 100A, 100A
In B and 100C, an open portion, that is, a C-shaped unconnected portion faces inward. The three groove heating conductors 100A, 100A
B, the open part of 100C is connected to the connection part 11
0A, 110B and 110C.

The connection portions 110A, 110B, 110C
Are located on both sides of a line WL connecting the center point W0 of the tripod housing member W and the center of the groove W1, as shown in FIG.

On the other hand, the groove heating conductor portions 100A, 100B,
100C, the connecting conductor 200A that connects the groove heating conductors 100A and 100B is formed in a vertically elongated substantially concave shape, and a pair of first connecting conductors 210A and 210A.
And a second connection conductor 220A that connects the first connection conductors 210A to each other. That is, the upper end of one first connection conductor 210A is
A of one connecting portion 110A is connected to the other first connecting conductor 210A.
The upper end of A is one connecting portion 11 of the groove heating conductor 100B.
0B.

The first connection conductor 2 of this connection conductor 200A
10A and 210A are groove heating conductor parts 100A and 100B
Are provided in a direction substantially perpendicular to the direction. Therefore, the first connection conductors 210A, 210A are parallel to the center axis of the tripod housing member W (the axis passing through the center point W0 shown in FIG. 2 and perpendicular to the plane of the drawing).

The connection conductor 200B for connecting the groove heating conductors 100A and 100C is also the same as the connection conductor 200A described above.
Want to be configured in the same way.

Therefore, the first connection conductors 210B and 210B of the connection conductor 200B are also connected to the connection conductor 200A described above.
Similarly to the first connection conductors 210A, 210A, the first connection conductors are vertically provided in a direction substantially orthogonal to the groove heating conductors 100B, 100C. Therefore, the first connection conductors 210B, 210B
Are parallel to the central axis of the tripod housing member W.

Further, one first connecting conductor 210A of the connecting conductor portion 200A and one first connecting conductor 210A of the connecting conductor portion 200B are provided.
Between the connection conductors 210B, both first connection conductors 210
An insulator 400 (shown by oblique lines) is interposed so as not to short-circuit A and 210B.

On the other hand, the power supply conductor 300A is connected to the other connection 110C of the groove heating conductor 100C, that is, to the connection 110C to which the connection conductor 200A is not connected. Further, the power supply conductor 300B is connected to the other connection 110B of the groove heating conductor 100B, that is, the connection 110B to which the connection conductor 200B is not connected.
It is connected to the.

The power supply conductor 300A is connected to the connection conductor 200B.
Are parallel to one of the first connection portions 210B. An insulator 400 (see FIG. 2) for preventing short circuit is interposed between the power supply conductor 300A and the connection conductor 210B.

Similarly, the power supply conductor 300B is parallel to one first connection 210A of the connection conductor 200A. Then, the power supply conductor 300B and the first connection conductor 210A
And an insulator 400 for preventing short circuit.

The groove heating conductor 10 of the induction hardening coil
A core (not shown) made of, for example, ferrite or the like for concentrating the lines of magnetic force is attached to 0A, 100B, and 100C.

The portions heated by the groove heating conductors 100A, 100B, 100C are located below the groove heating conductors 100A, 100B, 100C of the induction hardened coil.
That is, an inner cooling jacket (not shown) for spraying the cooling liquid is provided on the inner peripheral surface of the groove W1. Since this inner cooling jacket is attached to the high frequency heating coil, it moves inside the tripod housing member W together with the high frequency quenching coil.

Further, in order to prevent overheating of the tripod housing member W, an outer cooling jacket for spraying a cooling liquid on the outer peripheral surface of the tripod housing member W is provided.

Next, the induction hardening of the inner peripheral surface of the tripod housing member W by the induction hardening coil configured as described above will be described. The tripod housing member W is placed on an outlet link (not shown) with the open side facing downward. As shown in FIG. 2, the fixed induction hardened coil is inserted into the tripod housing member W and moved downward. At this time, the groove heating conductors 100A, 100B, and 100C are of course inserted into the groove W1.

Since a high-frequency current is supplied to the high-frequency hardening coil, both left and right side surfaces W11, which are inner surfaces of the groove W1, are formed.
And the thin portion 12 between them is sequentially heated from below.
The high-frequency current is supplied from the power supply conductor 300A to the groove heating conductor 10.
0C → connection conductor 200B (first connection conductor 210B → second connection conductor 220B → first connection conductor 210B) → groove heating conductor 100A → connection conductor 200A (first connection conductor 2)
10A → second connection conductor 220A → first connection conductor 210
A) → Groove heating conductor 100B → Power supply conductor 300B or the reverse direction.

At this time, the first connection conductor 210A of the connection conductor portion 200A and the first connection conductor 210B of the connection conductor portion 200B adjacent thereto are connected.
Since the high-frequency currents flow in opposite directions to the connection conductor 210B, the electromagnetic action is canceled. First connection conductor 21
OA and the first connection conductor 210B do not contribute to heating of the tripod housing member W.

This is because the first conductor 2 of the connection conductor 200A
The same is true between 10A and the power supply conductor 300B, and between the first connection conductor 210B of the connection conductor 200B and the power supply conductor 300A.

The portion heated by the induction hardening coil is subjected to induction hardening by being cooled by the inner cooling jacket. Further, since the tripod housing member W is also cooled by the outer cooling jacket, the hardened layer formed by the induction hardening does not enter the hardened state extending to the outer peripheral surface.

The induction hardened coil according to the second embodiment of the present invention is different from the induction hardened coil according to the first embodiment in that the connection conductors 200A and 200B are different.
0. That is, the two connection conductors 200A, 20A in the induction hardened coil according to the second embodiment.
0B is a line WL in which the first connection conductors 210A and 210B connect the center point W0 of the tripod housing member W and the groove W1.
It is a point located above.

That is, in this induction hardened coil, the first connection conductor 210A of the connection conductor portion 200A and the first connection portion 210B of the connection conductor 200B are arranged in the front-rear direction when viewed from the center point W0 of the trip housing member W. Line up,
The first connection conductor 210B and the power supply conductor 300A of the connection conductor 200B are arranged in the front-rear direction when viewed from the center point W0, and the first connection conductor 210A and the power supply conductor 300B of the connection conductor 200A are separated from the center W0. As you can see, they are lined up in the front-back direction.

The induction hardened coil according to the second embodiment thus configured is the same as the induction hardened coil according to the first embodiment, except for the points described above.

Unlike the two embodiments described above, it is also possible to use coaxial tubes for the connection conductors 200A and 200B.

In the above description, the tripod housing member W has been described as an example of the bottomed cylindrical work, but the present invention is not limited to this. The present invention can be applied to any work having a bottom and having a plurality of grooves formed on the inner periphery.

Further, when the inner surface of the tripod housing member W is overheated by the induction hardening coil, the induction hardening coil is fixed and the tripod housing member W is moved downward. Since the quenched coil and the tripod housing member W may be relatively moved, the tripod housing member W may be fixed and the induction hardened coil may be moved upward, or the induction hardened coil may be The tripod housing member W may be moved upward toward the lower side.

[0039]

The induction hardening coil according to the present invention is an induction hardening coil for heating the inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on the inner surface, wherein the coil faces the inner surface of the groove. A plurality of groove heating conductors, a plurality of connection conductors interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair of power supply conductors connected to the groove heating conductor. Wherein the connection conductor has a pair of first connection conductors connected between connection portions of adjacent groove heating conductors, and a second connection conductor connecting the first connection conductors to each other. The connection portion is located on both sides of a line connecting a center point of the bottomed cylindrical work and a center portion of the groove, and the first connection conductor extends in a direction substantially orthogonal to the groove heating conductor portion. Has been established,
The adjacent first connection conductor is configured so that a current in the opposite direction flows.

Therefore, according to this induction hardening coil,
Optimal heating can be performed not only on the left and right side surfaces and the thin portion forming the inner circumferential groove of the bottomed cylindrical work, but also on the thick corner portion of the connecting conductor portion.

A high-frequency hardening coil for heating an inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on an inner surface thereof, comprising: a plurality of groove heating conductors facing the inner surface of the groove; A plurality of connection conductors for interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair of power supply conductors connected to the groove heating conductors, wherein the connection conductors are A pair of first connection conductors connected between the connection portions of the adjacent groove heating conductor portions, and a second connection conductor connecting the first connection conductors, wherein the connection portion has a bottomed cylinder The first connection conductor is located on a line connecting the center point of the workpiece and the center of the groove, the first connection conductor extends in a direction substantially orthogonal to the groove heating conductor, and the first connection conductor is adjacent to the first connection conductor. The conductor is configured so that a current flows in the opposite direction.

For this reason, as described above, the connecting conductor is optimal not only for the left and right side portions and the thin portion but also the corner portion of the thick portion, which constitute the inner circumferential groove of the bottomed cylindrical work. Heating can be performed. Further, the above effect is obtained by preventing overheating of the corner portion.

Further, when a coaxial tube is used for the connection conductor, in addition to the effect of preventing overheating of the corner, the coil efficiency is improved and the life of the induction hardened coil is extended.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an induction hardened coil according to a first embodiment of the present invention.

FIG. 2 is a schematic bottom view showing a relationship between the induction hardening coil and a tripod housing member as a bottomed cylindrical work according to the first embodiment of the present invention.

FIG. 3 is a schematic bottom view showing a relationship between an induction hardening coil and a tripod housing member as a bottomed cylindrical work according to a second embodiment of the present invention.

FIG. 4 is a schematic bottom view showing the relationship between a conventional induction hardening coil of this type and a tripod housing member which is a bottomed cylindrical work.

FIG. 5 is a schematic bottom view showing the relationship between another conventional induction hardening coil of this type and a tripod housing member as a bottomed cylindrical work.

FIG. 6 is a schematic bottom view of an example of a tripod housing member that is a bottomed cylindrical work.

[Explanation of symbols]

 100A, 100B, 100C Groove heating conductor 200A, 200B Connection conductor 210A, 210B First connection conductor 220A, 220B Second connection conductor 300A, 300B Power supply conductor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C21D 9/40 C21D 9/40 B

Claims (3)

[Claims] An induction hardening coil for heating an inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on an inner surface thereof.
A plurality of groove heating conductors facing the inner surface of the groove, a plurality of connection conductors interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair connected to the groove heating conductor. And a pair of first connecting conductors connected between the connecting portions of the adjacent groove heating conductors, and a second connecting conductor connecting the first connecting conductors to each other. A connection conductor, the connection portion is located on both sides of a line connecting the center of the bottomed cylindrical work and the center of the groove,
The high-frequency quenching coil, wherein the first connection conductor extends in a direction substantially orthogonal to the groove heating conductor portion, and a current flows in an opposite direction to the adjacent first connection conductor. 2. An induction hardening coil for heating an inner surface of a groove of a bottomed cylindrical work having a plurality of grooves formed on an inner surface thereof.
A plurality of groove heating conductors facing the inner surface of the groove, a plurality of connection conductors interconnecting adjacent groove heating conductors among the groove heating conductors, and a pair connected to the groove heating conductor. And a pair of first connecting conductors connected between the connecting portions of the adjacent groove heating conductors, and a second connecting conductor connecting the first connecting conductors to each other. A connection conductor, wherein the connection portion is located on a line connecting a center point of the bottomed cylindrical work and a center portion of the groove, and the first connection conductor has a groove heating conductor portion and Are extended in a direction substantially orthogonal to each other, and a current in the opposite direction flows through the adjacent first connection conductor. 3. The induction hardened coil according to claim 1, wherein a coaxial tube is used for the connection conductor.