JPH0243863Y2 - - Google Patents

Description

[Detailed description of the invention] -Field of industrial application- This invention relates to an induction hardening device used for hardening the raceway surface carved into the inner or outer ring of a bearing, and in particular to the shape of its high-frequency coil. be.

- Prior Art - As shown in FIGS. 4 and 5, a conventional high-frequency coil 5a of an induction hardening device 18a used for hardening a raceway surface 20 provided on an inner ring or an outer ring 19 of a bearing is a hollow coil 5a. A square tube is formed into a rectangular shape (see FIG. 7) when viewed from the front (hardened surface side), and its short sides are bent near the center to form a semicircular shape when viewed from the side.

The bearing 19 is heated by the induction hardening device 18a equipped with the conventionally shaped high-frequency coil 5a.
When trying to harden the raceway surface 20 of the raceway surface 20, as shown in FIG.
The hardening of No. 3 and 24 becomes deep, and the depth of hardening becomes uneven as a whole. This is because, as the frequency increases, high-frequency currents tend to concentrate on the protruding parts or the periphery of the conductor surface, and the protruding parts generally have a smaller heat capacity than other parts of the conductor. This is because the protruding portion or a similar portion is more likely to be heated by induction than the central portion.

Therefore, conventionally, the protruding portions 2 on both sides of the raceway surface 20
In order to prevent the hardening of the protruding parts 23 and 24 from becoming deep, cooling water was injected from an injection nozzle provided toward the protruding parts 23 and 24, thereby suppressing the temperature rise in these parts 23 and 24.

-Problems to be solved by the invention- In such a conventional device 18a, in order to harden the entire raceway surface 20 that has been induction heated by the high-frequency coil 5a, a water injection is provided near the side opposite to the moving direction of the high-frequency coil 5a. In addition to the holes, injection nozzles for locally cooling the protruding portions 23 and 24 on both sides of the raceway surface are required, making the device complicated.

Furthermore, in order to make the hardening depth of the raceway surface the same, the amount of cooling water jetted from the injection nozzle had to be adjusted, making the hardening work complicated and requiring skill.

The present invention aims to solve the above-mentioned problems and provide a raceway surface induction hardening device that can uniformly harden the raceway surface without providing a local cooling means such as an injection nozzle.

- Means for Solving the Problems - Explaining using the reference numerals attached to the drawings, the induction hardening device 18 according to the present invention has a side surface shape along the raceway surface 20 provided on the inner ring or outer ring 19 of the bearing. The high-frequency coil 5, which has a semicircular shape along the raceway surface 20 of the bearing, is continuously moved to harden the surface of the raceway surface 20 by high-frequency induction heating. It is characterized in that the shape (viewed from the side) is formed into an ellipse or an ellipse having a long axis in the direction in which the raceway surface 20 extends.

- Effect - By making the front shape of the high-frequency coil 5 into an ellipse or an oval having a long axis in the extending direction of the raceway surface 20 of the bearing, that is, the longitudinal end 25 of the high-frequency coil 5 is By making it arcuate when viewed from the side), as shown in Figure 6,
The length l of the heating surface of the coil facing the side edges 27, 27 of the raceway surface 20 is shorter than that of the conventional rectangular shape shown in FIG. Here, 2 in Figures 6 and 7
8 indicates a region of the raceway surface 20 of the bearing that faces the coil 5 or 5a at a certain moment during hardening. On the other hand, since the length d of the heating surface of the coil 5 facing the center 29 of the raceway surface 20 does not change, the protruding portion 23 of the raceway surface 20 of the bearing,
Only 24 is no longer heated locally,
The entire raceway surface can be hardened to a uniform depth without providing local cooling means.

-Example- Figures 1 to 3 show an example of the present invention, in which Figure 1 is a perspective view of the entire device, Figure 2 is a front view of the high frequency coil, and Figure 3 is a side view of the same. It is.

In the figure, 1 and 2 are electrode plates superimposed with an insulator 3 in between, 4 is a mounting hole drilled in the electrode plates 1 and 2 and the insulating plate 3, and 5 is a high-frequency coil. The coil 5 is a hollow rectangular tube made of a conductive material such as copper, bent into an elliptical shape when viewed from the front, and further bent into a semicircular shape when viewed from the side. 6 is a wire core fitted in the center of the high-frequency coil 5; 7 and 8 are neck parts extending vertically from the high-frequency coil 5; 9 and 1;
Reference numeral 0 denotes a large-diameter L-shaped electrode fixing part fixed to the tips of the neck parts 7 and 8, and 11 and 12 are cooling water inlets and drain ports provided in the fixing parts 9 and 10.
Reference numerals 13 and 14 indicate cooling pipes for the electrode plates provided around three sides of each of the electrode plates 2 and 3; 15 indicates cooling pipes 13;
Hoses 14 are interconnected, and 16 and 17 are water supply ports and drain ports provided at the tips of the cooling pipes.

Induction hardening device 18 formed in this way
is the raceway surface 2 provided on the outer ring 19 of the bearing.
It is attached to the arm which is driven to rotate along the axis 0 through the attachment hole 4, and is also connected to a high frequency generation power source at the same time.
When hardening, place the high frequency coil 5 on the outer ring 1.
facing the orbital surface 20 of No. 9 at a predetermined distance,
Cooling water is passed through the water supply ports 11 and 16 to the coil 5.
is continuously moved along the raceway surface 20 while passing a high frequency current through it. 26 in Fig. 1 is the high frequency coil 5
A cooling water inlet is provided on the opposite side of the moving direction of the high-frequency coil 5 to rapidly cool the raceway surface 20 heated by the cooling water, and the raceway surface is continuously hardened while the device is moved in the direction of the arrow in FIG. I do.

-Effects- According to the induction hardening device for the raceway surface of the present invention, the protruding parts on both sides of the bearing raceway surface are not locally overheated, and the entire raceway surface is hardened to a uniform depth. be able to. Therefore, there is no need for special means such as injection nozzles for locally cooling the raceway surface, so the structure of the device is simple, and hardening does not require skill, making the work simple.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a perspective view of the entire device, FIG. 2 is a front view of the high-frequency coil, and FIG. 3 is a side view of the same. 4 and 5 show a conventional device, with FIG. 4 being a perspective view of the entire device, and FIG. 5 being an explanatory diagram showing the hardening depth of the bearing raceway surface.
Figures 6 and 7 are explanatory diagrams showing the differences in operation between the hardening device of this invention and the conventional hardening device, and Figure 6 is a partial development of the raceway surface showing the area facing the coil of this invention. 7 are partially developed views of the raceway surface showing the area facing the conventional coil. In the figure, 1: electrode plate, 2: electrode plate, 3: insulator,
5: High frequency coil, 6: Wire core, 7, 8: Cervical part,
9, 10: Electrode fixing part, 18: Hardening device, 1
9: Bearing outer ring, 20: Raceway surface, 23,2
4: Projection portion, 27: Area facing the coil.

Claims (1)

[Scope of utility model registration request] A high-frequency coil 5 whose side surface is semicircular along the raceway surface 20 provided on the inner ring or outer ring of the bearing is continuously moved to harden the surface of the raceway surface by high-frequency induction heating. An apparatus for induction hardening of raceway surfaces, characterized in that the front shape of the high-frequency coil 5 is formed into an ellipse or an ellipse having a long axis in the extending direction of the raceway surface 20. .