JPS59177892A - High frequency coil for moving and quenching cylindrical inner peripheral orbit groove with irregular thick unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency coil for moving and hardening an inner circumferential orbit groove of a cylindrical part having uneven wall thickness, such as an outer shell part of a constant velocity joint of an automobile.

FIG. 1 shows a constant velocity joint outer shell member 1 which is an automobile part, and both sides of the inner circumferential groove 2 are hardened. However, since the cross-sectional wall thickness shape of this kind of parts differs significantly depending on each part, it is necessary to reduce the amount of distortion and prevent cracking by quenching. It was extremely difficult to uniformly heat the surface.

Therefore, conventionally, as shown in FIGS. 2 and 3, a high frequency waveform having a shape as shown in the figure is inserted 2 along each inner circumferential orbit groove 2 of the member 1 to a predetermined depth in the axial direction. The transfer surface 2a of each persistent groove 2 is hardened in one shot using the coil 5,
A method of forming a hardened layer T has been adopted.

However, the hardened layer 'r that is simultaneously hardened by the continuous resonant frequency coil 5 shows a pattern shown in FIG. It is known that the hardness changes rapidly in the alternating parts 4 with the connecting inner surface 31) of the thin-walled parts 3, which may crack due to stress concentration in these parts, resulting in insufficient fatigue strength. .

As a solution to this problem, a hardening pattern electrode as shown in FIG. 4(5) is required. That is, as is clear from the figure,
Hardening is performed from the intersection point 4 of the transfer surface 2a and the connection inner surface 3b of the thin wall portion 3 connected to the transfer surface 2a to the connection inner surface 3b side to maintain sufficient hardness at the intersection point 4 and increase the strength of this portion. As an improvement measure, raising the level is required.

However, it is very difficult to obtain the hardening pattern TI using the conventional coil 5, and it is easy to obtain the hardening pattern T2 as shown in FIG. 4 (13).

That is, when heating is performed to sufficiently harden the intersection portion 4, the thin wall portion 3 tends to be overheated, and even if the thin wall portion 3 is cooled from the outer periphery 3a, the hardened layer of the thin wall portion 3 becomes deeper as shown in the figure.
It was easy to get into what is called a simmering state.

The present invention aims to solve the above-mentioned problems, and the gist of the present invention is to provide a high-frequency coil for movable hardening of a continuous groove on the periphery of a cylindrical body having unequal wall thickness. Each of the above-mentioned coils was electrically divided at a corresponding arrangement position, and at the divided position, a current was allowed to flow perpendicularly along the intersection of a pair of rolling surfaces and an inner circumferential groove connecting the rolling surfaces. There is a particular thing.

Embodiments of the present invention will be described below with reference to the drawings.

Note that the same elements as those in the conventional example described above are indicated by the same symbols.

5 to 10 show an embodiment of the present invention, and FIG. 5 shows a cylinder having uneven wall thickness by an induction hardening device 6 configured using a high-frequency coil 7 according to the present embodiment. When hardening the inner surface of a housing member as a shaped body,
This is a perspective view of the thick part showing the arrangement of the body. FIG. 6 is a perspective view of FIG. 5 seen from above. 1. FIGS. 7 to 10 show the high frequency coil 7 according to this embodiment.

The high-frequency coil 7 according to this embodiment is formed of a copper pipe that can be water-cooled by circulating cooling water inside the hollow interior, as shown in FIGS. 7 to io.

Further, in this embodiment, the high frequency coil 7 is inserted and disposed within three persistent grooves 2 of a housing member 1 having unequal thickness parts used in constant velocity joints of automobiles. , Correspondingly, as shown in FIG. 9, it consists of unit coils 7a, 7b, and 7c respectively distributed to each persistent groove 2.

Each unit coil 7a, 7b, 7c has a corresponding track→
A portion located inside 1b and 20 and corresponding to a pair of symmetrically formed transfer surfaces 2a is formed in an arc shape while staying on the transfer surfaces 2a, and is formed at a constant distance from the transfer surfaces 2a. An arcuate loop portion 8 is formed as a heating conductor.

Further, at a position corresponding to the intersection 4 between the pair of transfer surfaces 2a in each persistent groove 2 and the connection inner surface 3b of the thin wall portion 3 that connects the transfer surfaces 2a, the coil 7 is rotated toward the intersection 4. They are extended parallel to each other at a predetermined bonding interval to be arranged perpendicularly along the intersection point 4, and this is done in order to centrally heat the area around the intersection point 4. It is something. In other words, each unit coil 7a, 71
).

Both ends of the arcuate loop 8 of 7C are bent from the horizontal direction to the vertical direction at a position corresponding to the intersection portion 4, and the vertical portions 9 and 10 of each unit coil pair are bent upward by a predetermined length. After that, the unit coils are bent inward, and the unit coils are connected to each other in the horizontal plane as shown in FIG.

The ends of the horizontal portions are extended upward as vertical coils 71 and 72, function as lead pipes as will be described later, and are connected to a high frequency power source (not shown).

Therefore, in the high-frequency coil 7 according to the present embodiment, only the ends of the vertical coils 71 and 72 indicated by - are separated, and the other parts are continuous, and the entire coil 7 is separated. ] A large current of image frequency flows at 1 n, and cold water flows inside the instep.

In addition, the L vertical portions 9.1.0 of each unit coil 7a, 71), 7C have internal dimensions of lQ+u+ or more (ζ1
They should be placed one space apart to completely prevent mutual electrical interference.

In this embodiment, the induction hardening apparatus 6 including the high-frequency coil 7 having the above-mentioned configuration is constructed as follows.

It is equipped with six induction hardening devices, a heating means 2o, an internal unit 16 consisting of a first cold shoulder jacket 3, and a second cooling jacket 5.

As shown in FIGS. 5 to 9, the internal unit 16
In this embodiment, the upper dd
According to the shape of the high-frequency coil 7, the coils are divided equally into three directions, and are arranged in three locations in total.

The heating means 2] and the first cooling jacket 3 constituting the internal unit 16 are connected to the induction hardening device 6 as shown in FIG.
The heating means 20 is integrally formed along the elevating direction ( ) and the axial direction of the housing part 1 so that the heating means 20 is located on the left side of the elevating direction and the first cooling jacket 13 is located below.

As shown in FIGS. 7 and 8, the heating means is applied to the high frequency coil 7 and the magnetic material 11 such as a dust core.
and 12.

The magnetic material 11 covers the upper and lower side surfaces and the inner surface of the arcuate loop portion 8 of the high-frequency coil 7, and covers the transfer surface 2a of each housing 1.
The magnetic body [F] 2 is mounted so as to release only the side surface 81 facing the high-frequency coil 7,
Of 10, surfaces 91 and 101 cover the side facing the connection (c) and 3b of the housing member 1 and are disposed facing the intersection portion 4 of the transfer surface 2a and the connection inner surface and the transfer surface 2b.
The structure is such that the induction heating effect of each high-frequency current is enhanced by opening only one of the two.

In this embodiment, the first cooling jacket 13 is assembled integrally with the F section of the heating means 20 as shown in FIGS.
2, a predetermined number of coolant nozzles 133 are radially drilled in the vicinity of the intersecting point 4 of the continuous groove 2 [ftj 2a and the rolling surface 2a and the inner peripheral surface 3b connected thereto]. It is configured to be able to spray liquid.

Note 1. The direction of the nozzle is slightly oriented F in FIGS. 7 and 8.

Like the heating means 20, the first cooling jackets 13, which are equally divided into three directions, are each connected to a cooling liquid pressure feed pipe 14 arranged inside one columnar body through a communication pipe (not shown). The upper part of the pressure feeding pipe 14 is connected to a cooling liquid tank (not shown), and the cooling liquid is forced into each of the cooling jackets 13 by an appropriate pressure feeding means.

In this embodiment, as shown in FIG. 9, the second cooling jacket 15 is arranged facing the outer peripheral surface 3a of the thin wall portion 3 connected to the E rolling surface '2a of the housing member 1 at a predetermined interval during hardening. Outer circumferential surface 3 of the thin wall portion 3 of the thin wall inner wall 152 forming the hollow portion 151.
A predetermined number of nozzles 153 are bored on the surface facing a,
Coolant is supplied through a pressure feed pipe 154 connecting the cooling jacket 15 and a coolant tank (not shown).

As shown in FIG. 5, the internal unit 16 and the second cooling jacket 15 are arranged to protrude from the base 17 by approximately the same length.

Next, the operation of this embodiment will be explained.

When the transfer surface 2a of the housing member 1 is hardened by the induction hardening device 6 having the above-mentioned frequency coil 7, the housing member 1 is fixed at a predetermined position without trenches as shown in FIG. The induction hardening device 6 disposed directly above it is lowered downward at a predetermined speed by an appropriate elevating means.

As shown in FIGS. 7 and 8, the high-frequency coil 7 of the pigeon-wave hardening device 6 passes through the hollow part from the upper end opening 1a of the housing member 1 and reaches the vicinity of the lower end opening lb, and at the same time, A high frequency current is passed through the coil 7 from a power source (not shown) connected to the ends of the coils 71 and 72;
At that position, the constant heating of the transfer surface 21) facing the 1st column 7 is heard, and when the quenching temperature of the square is reached, the same rib... ”; moving toward the direction heating starts.

At the same time that the footrest heating is finished and the moving heating is started, the first coil 7 placed below the coil 7 is heated. 'Going Jacket 13
From there, cooling 1 night is injected towards the 7 heated 1ni,
The heated object is rapidly cooled and hardening is started, and a predetermined hardened layer 'P is obtained from the continuous groove transfer part 2a to the connecting intersection part 4 to the connecting inner surface 31].

At this time, as shown in FIG. 9, the vicinity of the intersection 4 between the rolling surface 2a of the No-Ujifugu member l and the connecting inner surface 3b connected to the rolling surface 2a and the vertical portion 9°]0 of the coil 7 Since they are arranged in a corresponding manner, a large current flows in the vicinity of the intersection point 4, and the vicinity of the intersection point 4 does not become insufficiently heated. Furthermore, since the cooling liquid is injected from the second cooling jacket 15 onto the outer circumferential portion 3a of the thin wall portion 3 prior to or in parallel with the heating of the upper portion 3, the portion near the intersection portion 4 is heated. The depth can be adjusted tii) immediately by changing the injection quantity, and the quenching depth by the first quenching jacket j3 also becomes relatively shallow.

Therefore, the rolling surface 2a of the housing member 1 to be hardened
The induction hardened layer T can be obtained evenly and uniformly, and shrinkage deformation of the transfer surface 2a during hardening, which occurs in conventional hardened products, can be prevented.

Therefore, there is no need for correction work in the post-process, and life-saving properties are improved. Furthermore, as mentioned above, stress is concentrated at the intersection 4 between the rolling surface 2a and the connecting inner surface 3)), which reduces fatigue strength and causes quench cracking, etc. Since the hardened layer T1 is formed so as to cover the connection inner circumferential surface 3a without causing the hardened layer T to form at the intersection portion 4, this can be reliably prevented.

As shown in FIG. 5, when the induction hardening device 6 is raised and a hardened layer T1 is formed near the upper end opening of the housing member 1, the conduction of the high frequency current to the coil 7 is cut off.
After that, the induction hardening device 6 can be raised.

In the above embodiments, the nozzling member 1 was used as the object to be hardened, but the high-frequency coil 7 according to the present invention can be applied to the internal hardening of any other cylindrical body having an uneven wall thickness cross section. It is something that can be used.

[Brief explanation of drawings]

Figure 1 is an external view of the outer shell part of a constant velocity joint, Figure 2 is a conceptual diagram of a conventional high-frequency heating coil applied to the inner surface of a body to be hardened that has a cross section with unequal wall thickness, and Figure 3 is Figure 2. XX cross-sectional view of
Fig. 4 (5) is a cross-sectional view of the main part showing the pattern of the desired hardened layer, Fig. 4 (13) is a cross-sectional view of the main part of the hardened layer of the conventional coil, and Figs. An embodiment of the invention is shown, and FIG. 5 is a perspective view of essential parts showing an aspect of the arrangement before hardening of an induction hardening apparatus having a housing member and a high-frequency coil according to the invention, and FIG. FIGS. 7 and 8 are longitudinal sectional views of the main parts showing the arrangement of the high-frequency coil during hardening, and FIG. 9 is a perspective view of the main parts of the high-frequency coil according to the present invention as viewed from above. Embodiment and moment seen from above. 5A is an explanatory diagram showing the direction of the three-frequency current, and FIGS. 7 and 8 are cross-sectional views taken along Y, Y and Z-Z in FIG. 9, respectively, and FIG. 10 is a diagram showing the sieve frequency according to the present invention FIG. 2 is a perspective view of main parts showing the configuration of a coil. 1. Constant velocity joint outer shell removal, 2. Relentless groove, 3.
...Connection part, 4...Intersection part, 6
...Induction hardening device, 7...-High frequency coil, 8... Arc-shaped loose part, 9, 10...
・Vertical part, ]3...First cooling jacket, 15
...Second cooling jacket. Figure 6

Claims (1)

[Claims] (1) In a high-frequency coil for moving and quenching the inner circumferential orbital groove of a cylindrical member having uneven wall thickness parts, a pair of rolling grooves forming each of the inner circumferential orbiting grooves described in - and this rolling surface A pair of intersecting heating conductors extending perpendicularly along the intersecting points at a predetermined coupling interval parallel to the intersecting points with the inner surfaces of the connecting parts that connect each other, and the above pair of transfer surfaces. 1. Form a circular arc shape horizontally. The total uniformity of the conductor is that it forms a combined conductor with the transfer surface heating conductor loop.
High frequency coil for movable hardening of inner circumferential orbit groove of cylindrical part having thick part 1.2) Claim 1, wherein the cylindrical member is an outer shell part of a constant velocity joint for an automobile. The described high-frequency coil for moving hardening.