JPH073325A - Device for heating base stock for forming - Google Patents

Abstract

PURPOSE:To provide a device for heating a base stock for forming which uniformly heats the whole bar-like base stock having different diameters and has a simple constitution and excellent versatility. CONSTITUTION:In this device, a shifting means 22 intermittently feeding the bar-like base stock 10 in the axial direction and a high frequency induction coil 24 wound around the outer periphery of this base stock 10 and arranged on the carrying path of the bar-like stock 10 are provided. The high frequency induction coil 24, is provide with a first coil portion 32 having narrow width set to a first coil pitch P1, a second coil portion 34 having wide width set to a second coil pitch P2 largely separated from the first coil pitch P1, a third coil portion 36 having wide width set to a third coil pitch P3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for heating a molding material for heating a material to be hot forged by high frequency to a predetermined temperature before molding.

[0002]

2. Description of the Related Art A hot forging method is widely adopted in which a material heated to a predetermined temperature, for example, about 1000.degree. C. is put into a molding die and the material is pressed to obtain a molded article having a predetermined shape. There is.

By the way, there are various shapes of materials formed by this kind of hot forging method, and for example, connecting rods (hereinafter referred to as connecting rods) have different outer diameters along the axial direction. In many cases, the rod-shaped material that they have is used. At that time, it is necessary to uniformly heat the entire rod-shaped material prior to forming.Therefore, the winding diameter is set to be a substantially constant distance from the outer circumference of the different-diameter material along the axial direction. There is proposed a heating device in which a high frequency coil is arranged by changing the temperature (see Japanese Patent Application Laid-Open No. 4-232210).

[0004]

However, in the above-mentioned prior art, the high frequency coil is formed in a different diameter shape in the axial direction corresponding to the outer diameter shape of the desired material. Therefore, if the diameter of the material changes in response to a change in the material, the distance between the high frequency coil and the outer circumference of the material changes, and the entire material cannot be heated uniformly. It has been pointed out that this makes it difficult to deal with various materials having different diameters.

The present invention is intended to solve this kind of problem, and is capable of uniformly heating various rod-shaped raw materials having different diameters as a whole, and having a simple construction and excellent versatility. An object of the present invention is to provide a heating device.

[0006]

In order to achieve the above object, the present invention provides a heating device for heating a rod-shaped material having different outer diameters along the axial direction to a predetermined temperature prior to forming. A high-frequency coil, comprising: a transfer unit that intermittently feeds the rod-shaped material in the axial direction; and a high-frequency coil that circulates around the outer periphery of the rod-shaped material and is arranged in a conveyance path of the rod-shaped material. A first coil portion provided at a stop position of the rod-shaped material corresponding to a small diameter portion of the rod-shaped material and set to a predetermined first coil pitch; and a stop position of the rod-shaped material A second coil portion provided corresponding to the large diameter portion of the rod-shaped material and having a second coil pitch spaced apart from the first coil pitch by a larger distance.

Further, the high-frequency coil has a third coil portion which is provided integrally with the first and second coil portions and on the downstream side in the transfer direction of the rod-shaped material for keeping the heat of the entire rod-shaped material. It is preferable.

[0008]

In the heating apparatus for molding material according to the present invention described above, the rod-shaped material that is intermittently fed on the conveying path has its small diameter portion induction-heated by the first coil portion of the high-frequency coil at its stop position. The large diameter portion is induction-heated by the second coil portion. Here, since the first coil pitch of the first coil portion is dense and the second coil pitch of the second coil portion is coarse, it is possible to supply appropriate electric power to the small diameter portion and the large diameter portion, respectively. it can. Therefore, a rod-shaped material having different outer diameters along the axial direction can be uniformly heated as a whole, and various rod-shaped materials having different diameters can be heated only by changing the first and / or the second coil pitch. It becomes possible to cope easily.

Further, since the rod-shaped material that has passed through the first and second coil portions is arranged corresponding to the third coil portion, the entire rod-shaped material is kept warm at a predetermined temperature in a uniform state.

[0010]

EXAMPLES Examples of the heating apparatus for the molding material according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 3, reference numeral 10 indicates a rod-shaped raw material for forming a connecting rod, which is heated to a predetermined temperature by the heating device 20 according to this embodiment prior to forming. The rod-shaped material 10 includes a first large-diameter portion 12 and a second large-diameter portion 14 having different outer diameters and different lengths at both ends, and the first and second large-diameter portions 12 and 14 are provided.
The small-diameter portion 16 is integrally provided via the tapered portion.

As shown in FIGS. 1 and 2, the heating device 2
0 is a rod-shaped material 10 (including 10a to 10c, hereinafter,
The same) is intermittently sent in the axial direction (direction of arrow A), so-called tact feed, and a high-frequency coil 24 arranged around the outer circumference of the rod-shaped material 10 and arranged in the conveying path H of the rod-shaped material 10. With.

Both ends of the high-frequency coil 24 are terminal plates 2
The cooling water is connected to the high frequency power supply 28 via 6 and the cooling water is circulated therein via the cooling water pipes 30a and 30b (see FIG. 1).

The high frequency coil 24 is a narrow first coil provided at the stop position of the rod-shaped material 10 so as to correspond to the small diameter portion 16 of the rod-shaped material 10 and set to a predetermined first coil pitch P1. The part 32 and a second coil which is provided at a stop position of the rod-shaped material 10 in correspondence with the first and second large diameter portions 12 and 14 of the rod-shaped material 10 and which is separated from the first coil pitch P1 by a large distance. And a wide second coil portion 34 set to the pitch P2. The high frequency coil 24 further includes first and second coil portions 32, 3
4, and a wide third coil portion 36 for keeping heat of the entire rod-shaped material 10 is provided on the downstream side in the transfer direction (arrow A direction) of the rod-shaped material 10. The third coil portion 36 is longer than the axial length of the rod-shaped material 10 and is set to a predetermined third coil pitch P3.

The transfer means 22 is provided with a ceramic cylindrical body 38 arranged inside the high frequency coil 24, and a plurality of rod-shaped materials 10 have their respective end portions in a conveying path H formed in the cylindrical body 38. They are placed in contact with each other. In the cylindrical body 38, the rod-shaped material 10a arranged in the uppermost stream in the direction of arrow A
A pusher 40 that engages with the end of the rod is provided, and the pusher 40 is configured to intermittently feed a plurality of rod-shaped materials 10a in the direction of arrow A via an actuator (not shown). An inclined chute member 42 is provided at the downstream end of the cylindrical body 38 in the direction of arrow A, and the rod-shaped material 10 conveyed by this chute member 42 is put into a hot forging die (not shown).

Next, the heating device 20 constructed as described above.
The operation of will be described.

First, as shown in FIG. 1, a plurality of rod-shaped materials 10a to 10c are arranged in a cylindrical body 38 with their ends abutting each other, and a high frequency power source 28 is driven. As a result, a high frequency current flows through the high frequency coil 24. Therefore, the rod-shaped materials 10a to 10c arranged in the high-frequency coil 24 via the tubular body 38 are induction-heated by the high-frequency current.

In this case, in the rod-shaped material 10a, the small diameter portion 16 is arranged corresponding to the first coil portion 32, and the first large diameter portion 12 is arranged corresponding to the second coil portion 34. There is. Here, the first coil portion 32 is
The second coil portion 34 is a narrow portion set to a relatively small first coil pitch P1, while the second coil portion 34 is separated from the first coil pitch P1 by a second coil pitch P1.
It is a wide part set to 2. Therefore, desired power can be supplied to the small diameter portion 16 and the first large diameter portion 12 having different diameters, and the small diameter portion 16 and the first large diameter portion 12 can be heated substantially uniformly. It will be possible.

Next, the pusher 40 constituting the transfer means 22 advances, the rod-shaped material 10a is in the position of the rod-shaped material 10b, this rod-shaped material 10b is in the position of the rod-shaped material 10c, and further this rod-shaped material 10c is the chute member 42. It is dispensed through and put into a molding die (not shown). The rod-shaped material 10a that has reached the position of the rod-shaped material 10b is positioned such that the second large diameter portion 14 thereof corresponds to the second coil portion 34. Therefore, the second large-diameter portion 14 has the first large-diameter portion 12 described above.
A desired heating state can be obtained in the same manner as in.

Further, when the rod-shaped material 10a reaches the position of the rod-shaped material 10c under the action of the transfer means 22, the heat retaining state is maintained over the entire length of the rod-shaped material 10a via the third coil portion 36. As a result, the rod-shaped material 10a is
The whole is heated and maintained at a uniform temperature, and is conveyed from the chute member 42 into a molding die (not shown).

As described above, in this embodiment, the small diameter portion 16 of the rod-shaped material 10 is heated by the first coil portion 32 in which the pitch of the high frequency coil 24 is set to the dense first coil pitch P1, while the pitch is coarse. The first and second large diameter portions 12 and 14 of the rod-shaped material 10 are heated by the second coil portion 34 set to the second coil pitch P2. Therefore, the magnetic flux density is changed corresponding to the different diameter portions of the rod-shaped material 10, and the different diameter portions, that is, the small diameter portion 16 and the first and second large diameter portions 12 and 14 are heated to a uniform temperature. The effect of being able to do is obtained. Moreover, since the entire rod-shaped material 10 is kept warm by the third coil portion 36 provided in series with the first and second coil portions 32 and 34, it is possible to adjust the temperature of the rod-shaped material 10 to a uniform temperature as a whole. become.

FIG. 4 shows the temperature distribution of each part of the rod-shaped material 10 when an experiment for heating the rod-shaped material 10 with the heating device 20 is performed. From this, it is understood that the respective parts of the rod-shaped material 10 which are different-diameter members are heated to substantially the same temperature with high accuracy.

Furthermore, in this embodiment, the rod-shaped material 10 is used.
When various rod-shaped materials having different shapes from are used, it is only necessary to change the first coil pitch P1 and / or the second coil pitch P2 of the high frequency coil 24. For this reason,
There is an advantage that various materials having different diameters, such as the rod-shaped material 10 can be uniformly heated as a whole, and the versatility is excellent with a simple configuration.

[0024]

The heating device for a molding material according to the present invention has the following effects.

The rod-shaped material that is intermittently sent on the transport path is
At the stop position, the small-diameter portion is induction-heated by the first coil portion of the high-frequency coil, while the large-diameter portion is induction-heated by the second coil portion. Here, since the first coil pitch of the first coil portion is dense and the second coil pitch of the second coil portion is coarse, it is possible to supply appropriate electric power to the small diameter portion and the large diameter portion, respectively. it can. Therefore, it is possible to uniformly heat the rod-shaped material having different outer diameters along the axial direction as a whole with a simple structure.
And / or by simply changing the second coil pitch, it becomes possible to easily handle heating of various rod-shaped materials having different diameters.

Further, since the rod-shaped material that has passed through the first and second coil portions is arranged corresponding to the third coil portion, the entire rod-shaped material is kept warm at a predetermined temperature in a uniform state, The heat treatment of the rod-shaped material is performed with higher accuracy.

[Brief description of drawings]

FIG. 1 is a front view showing the main part of a heating device for a molding material according to an embodiment of the present invention.

FIG. 2 is a side view of the heating device.

FIG. 3 is an explanatory diagram of a rod-shaped material heated by the heating device.

FIG. 4 is a heating temperature distribution chart of each part showing the result of an experiment of heating a rod-shaped material by the heating device.

[Explanation of symbols]

10, 10a, 10b, 10c ... Rod-shaped material 12, 14 ... Large diameter part 16 ... Small diameter part 20 ... Heating device 22 ... Transfer means 24 ... High frequency coil 32, 34, 36 ...
Coil part 38 ... Cylindrical body 40 ... Pusher 42 ... Shoot member P1, P2, P3 ...
Coil pitch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Kihara 1-10-1 Shin-Sayama, Sayama-shi, Saitama Honda Engineering Co., Ltd. (72) Inventor Hiroshi Sugita 1-10-1 Shin-sayama, Sayama-shi, Saitama Prefecture Engineering Co., Ltd.

Claims (2)

[Claims] 1. A heating device for heating a rod-shaped material having a different outer diameter along the axial direction to a predetermined temperature prior to molding, and a transfer means for intermittently feeding the rod-shaped material in the axial direction. And a high-frequency coil that circulates around the outer periphery of the rod-shaped material and is arranged in a conveyance path of the rod-shaped material, the high-frequency coil being at a stop position of the rod-shaped material and having a small diameter portion of the rod-shaped material. Corresponding to and predetermined first
A first coil portion set to a coil pitch, and a second coil pitch provided at a stop position of the rod-shaped material corresponding to a large-diameter portion of the rod-shaped material and separated from the first coil pitch by a larger distance. And a second coil portion that has been formed. 2. The apparatus according to claim 1, wherein the high-frequency coil is provided integrally with the first and second coil parts and on the downstream side in the transfer direction of the rod-shaped material to retain heat of the entire rod-shaped material. A heating device for a molding material, comprising a third coil portion for: