JPH0696747B2 - Hardening device for camshaft - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for quenching / hardening a cam shaft that drives an air supply / exhaust valve in an automobile engine or the like, and more particularly to a cam portion of the cam shaft. The present invention relates to a quenching device for a camshaft that quenches using induction heating with a high frequency current.

[Prior Art] Generally, a camshaft that drives an air supply / exhaust valve is
As shown in the drawing, the cam 1A is attached to the cam shaft 1, and the cam shaft 1 is rotationally driven to press a tappet (not shown) by the outer circumference of the cam 1A, thereby driving the supply / exhaust valve and the like. It has become so.

Since the cam 1A continues to contact the tappet with a predetermined pressing force in this way, in order to increase the strength of the outer periphery of the cam 1A, conventionally, induction heating with a high frequency current is used to heat the outer peripheral surface of the cam 1A. It is hardened by hardening.

Conventionally, as a camshaft quenching device of this type,
There is something like the one shown in the figure. This quenching device is composed of a coil member 2 connected to a high-frequency current (not shown). When heating and quenching the cam 1A, a cam shaft is inserted into the coil member 2, The coil member 2 is arranged on the outer periphery of the cam 1A.

When a high-frequency power source is connected to the coil member 2 and a high-frequency current is passed, the electromagnetic induction action from the coil member 2 causes the cam 1A made of a good conductor to approach the coil member 2 due to the eddy current generated on its surface. Heat is generated on the outer peripheral surface of the cam 1A, and the outer periphery of the cam 1A is heated and quenched. The camshaft is constantly driven to rotate during quenching.

[Problems to be Solved by the Invention] Normally, the camshaft 1 of the camshaft is provided with as many cams 1A as the number of cylinders. However, as shown in FIG. Often, a plurality (two in FIG. 5) of cams 1A having different phases are provided close to each other, such as for intake valves and exhaust valves for the same cylinder. In such a case, when simultaneously quenching each of the cams 1A, 1A using the conventional camshaft quenching apparatus as described above, as shown in FIG. After being inserted into the member 2 and arranged so that the position of each cam 1A and the position of the coil member 2 correspond to each other, a high frequency current is applied.

At this time, the magnetic field of the coil member 2 is extended so that it can reach nearby members as shown by the thin line a in FIG.
The surface of the cam top 1A-1 and the surface of the base circle 1A-2 in each cam 1A are different in distance from the axis of the cam shaft 1 in each cam 1A. For this reason, in particular, when the interval between the adjacent cams 1A, 1A is narrow as shown in FIG. The cam tops 1A-1 of the adjacent cams 1A make it difficult for induction heating to occur, and the heating temperature becomes lower than that of the portion B.

Therefore, in the conventional quenching device, heating unevenness is likely to occur,
Each cam 1A cannot be hardened and hardened uniformly.

Further, in the conventional quenching apparatus, the coil member 2 is used during quenching work.
Another problem is that it is difficult to set because the camshaft is inserted therein.

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and provides a quenching device for a camshaft, which can uniformly heat and quench the cam portion and can easily set the camshaft. The purpose is to

[Means for Solving the Problems] Therefore, in the quenching device for a camshaft of the present invention, the coil member connected to the high-frequency power source is provided with the camshaft from both sides along the axial direction of the camshaft. A pair of U-shaped high-permeability members are provided in the pair of conductor portions, respectively, according to the position of the cam portion on the cam shaft. It is characterized in that the openings are attached so as to face each other.

[Operation] In the above-described quenching device for a camshaft of the present invention, the pair of conductor portions of the coil member are arranged so as to sandwich the camshaft from both sides along the axial direction of the camshaft of the camshaft. Since a pair of U-shaped high-permeability members are arranged in the pair of conductor portions with their openings facing each other depending on the position of the portion, when a high-frequency current is passed from the high-frequency power source to the coil member, The magnetic field formed by the conductor portion and the high magnetic permeability material is uniformly formed only toward the predetermined cam portion. Therefore, the surface of the cam portion of the camshaft is uniformly heated and quenched by induction heating.

[Embodiment] A quenching apparatus for a camshaft as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view thereof, and FIG.
The drawing is an enlarged sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a perspective view showing the main part thereof.

As shown in FIGS. 1 to 3, the quenching apparatus of this embodiment has a coil member 4 connected to a high frequency power source 5. The coil member 4 includes a pair of conductor portions 4
A, 4A, a pair of power source connecting portions 4A-1, 4A-1, and a pair of end conductor portions 4A-2, 4A-2.

Here, the pair of conductor portions 4A, 4A are arranged so as to sandwich the cam shaft 1 from both sides along the axial direction of the cam shaft 1 of the cam shaft, and the power source is connected from the vicinity of the center of the one conductor portion 4A. The parts 4A-1 and 4A-1 are led out and connected to the high frequency power supply 5. Further, at both ends of the pair of conductor portions 4A, 4A, the end portions of the conductor portions 4A, 4A are connected by the end conductor portions 4A-2, 4A-2. Further, each of the end conductor portions 4A-2, 4A-2 has a semicircular shape so as to allow the cam shaft 1 and the cam shaft end member 3 to extend in the axial direction, as shown in FIGS. Is formed in.

Then, in the pair of conductor portions 4A, 4A, a pair of U-shaped high-permeability members 4B, 4B respectively have their openings opposed to each other according to the arrangement position of the cam 1A on the cam shaft 1. Thus, the conductor portions 4A, 4A are fitted and attached from the outside.

As the high-permeability materials 4B and 4B, pure iron, silicon steel plates (including laminated silicon steel plates), etc. are used. Also,
The pair of high magnetic permeability materials 4B, 4B are arranged and set according to the position and number of the cams 1A for each cam shaft to be quenched.

Since the quenching device for a camshaft as one embodiment of the present invention is configured as described above, the cam 1A of the camshaft is
When quenching the surface of, the cam shaft 1 of the cam shaft is sandwiched between the conductor portions 4A and 4A, and the position of the cam 1A and the high magnetic permeability material 4B are set as shown in Figs. The camshafts are arranged so that the positions 4 and 4B correspond to each other.

At this time, in the quenching apparatus of this embodiment, it is not necessary to insert the camshaft into the coil, and the semicircular end conductor portions 4A-2 and 4A-2 make it possible to use the camshaft 1 and the cam. Since the axial end member 3 is allowed to extend in the axial direction, the camshaft can be set to the quenching work state very easily.

After setting the cam shaft, when a high frequency current is passed from the high frequency power source 5 to the coil member 4 through the power source connecting portions 4A-1 and 4A-1, this current flows along the conductor portions 4A and 4A.
Flowing in the axial direction of the U-shaped high permeability material 4B, 4B
Are arranged so that their openings face the cams 1A corresponding to the positions of the cams 1A, the magnetic field formed by the conductor portion 4A and the high-permeability material 4B is shown by the thin line b in FIG. As described above, the high-permeability materials 4B, 4B are uniformly formed only toward the cam 1B toward which the openings are directed.

As a result, the surfaces of the plurality of cams 1A of the camshaft are simultaneously heated and quenched by induction heating to be hardened,
The surface strength of the cam 1A increases.

During the quenching work of the cam shaft, the cam shaft end members 3, 3 at both ends of the cam shaft are connected to a rotation driving unit (not shown), and the cam shaft is constantly driven to rotate.

Thus, according to the quenching apparatus of this embodiment, the conductor portion 4A
By applying a high-frequency current along the axial direction of the cam shaft 1 of the cam shaft, and by attaching the U-shaped high magnetic permeability material 4B to the conductor portion 4A corresponding to the position of the cam 1A,
A magnetic field directed only to the specified cam 1A is formed and is not affected by the adjacent cam 1A or the high-permeability material 4B.Therefore, heating unevenness does not occur and the cam 1A can be heated and hardened uniformly, and The camshaft can be set very easily during entry work.

In addition, in the above-mentioned embodiment, the plurality of cams 1A of the cam shaft are all hardened by one coil member 4, but the power of the high frequency power source 5 and the size of the cam shaft,
Depending on the number of cams, the coil member 4 may be divided into about 1 to 4 parts and the cam shaft may be set.

Further, if the high-permeability material 4B is slidably provided along the conductor portion 4A and the high-permeability material 4B can be fixed to the conductor portion 4A at a desired position, quenching of various camshafts can be easily performed. Besides, it is also possible to make fine adjustments so that the high magnetic permeability material 4B is in a position corresponding to the cam 1A.

[Effects of the Invention] As described in detail above, according to the quenching device for a camshaft of the present invention, the coil member connected to the high frequency power source is provided along the axial direction of the camshaft of the camshaft. A pair of U-shaped high-permeability members are formed in the pair of conductor portions according to the position of the cam portion on the cam shaft. Since a magnetic field directed only to a predetermined cam portion can be formed by an extremely simple structure in which the openings are opposed to each other, the cam is not affected by the adjacent cam portion or the high-permeability material. In addition to uniformly heating and quenching the part, the effect of setting the camshaft during quenching work is extremely easy.

[Brief description of drawings]

1 to 3 show a quenching device for a camshaft as one embodiment of the present invention, FIG. 1 is a plan view thereof, and FIG. 2 is an enlarged sectional view taken along the line II-II of FIG. FIG. 3 is a perspective view showing a main part thereof, FIGS. 4 and 5 show a conventional quenching device for a camshaft, and FIG. 4 is a perspective view showing a mounting state on the camshaft. FIG. 5 is a side view showing the state of simultaneous quenching of a plurality of cams. DESCRIPTION OF SYMBOLS 1 ... Cam shaft, 1A ... Cam, 3 ... Cam shaft end member, 4 ... Coil member, 4A ... Conductor part, 4A-1 ... Power supply connection part, 4A-2 ...
End conductor part, 4B ... High permeability material, 5 ... High frequency power supply.

Claims (1)

[Claims] 1. A quenching method for a cam shaft, comprising a coil member arranged on the outer periphery of the cam shaft and connected to a high frequency power source, for quenching a cam portion of a cam shaft by utilizing induction heating by a high frequency current. In the apparatus, the coil member is configured to include a pair of conductor portions arranged so as to sandwich the cam shaft from both sides along an axial direction of the cam shaft of the cam shaft, and the cam portion on the cam shaft. A pair of U-shaped high-permeability members are attached to the pair of conductor portions so that their openings are opposed to each other, depending on the arrangement position of. apparatus.