JPH0632283B2 - Billet heater - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a billet heater for induction heating by housing a billet in an induction heating coil.

Prior art and its problems In the conventional billet heater of this type, the billet heating coil has a length for accommodating several billets in the axial direction, and a predetermined number of billets are put in the heating coil. Efficient heating is performed when heated. Then, a new billet is pushed in from the rear side of the heating coil, and the billet in the heating coil is forwardly forwarded, whereby the billet on the front side is discharged to the outside of the heating coil. In this way the billet is usually heated continuously.

On the other hand, when using a new mold on a trial basis in an extruder or the like used in the process using this type of billet, or when making a first adjustment when replacing the mold, about 1 or 2 In some cases, a small number of billets are heated for testing. As a method of performing so-called test firing for heating for such a billet test, conventionally, a method of putting only a small number of one or two billets required for the test into a billet heater and heating the billet heater are matched with the rating of the billet heater. There is a method in which a large number of billets are placed in a billet heater and heated.

However, as described above, in the conventional billet heater, the heating coil has a length such that several billets can be continuously accommodated, so that a small number of one or two billets is inserted into the heating coil for heating. In this case, there is a problem that the heating efficiency is low and it is difficult to take the billet in and out of the heating coil. On the other hand, the method of charging a predetermined number of billets according to the length of the heating coil into the heating coil to heat the billets requires heating the billets in excess of the required number, so that the billet that has been excessively heated is wasted. .

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a billet heater capable of heating a small number of billets with high efficiency and without waste.

In order to achieve such an object, the present invention is used for normal operation, and an induction heating coil for normal operation having a coil length capable of charging a predetermined number of billets in the lengthwise direction thereof, and A power source for supplying electric power to the induction heating coil for normal operation, and the induction heating coil for normal operation, which are provided independently of each other, are used for test baking, and one or two billets are arranged in the longitudinal direction thereof. An induction heating coil for test baking having a coil length that can be loaded side by side, and a switch means for supplying required power to the induction heating coil for test baking from the power source are provided.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a billet heater main body, and a power source 2 for billet heating is provided in the lower half portion thereof. Reference numeral 3 denotes an induction heating coil for normal operation, which is provided on the upper part of the main body 1, and has a coil length such that the number of billets to be heated during normal operation, for example, four billets can be arranged in the longitudinal direction and charged. is doing.

A billet transport mechanism 4 feeds billets one by one into the heating coil 3 from one end A side.

Reference numeral 5 denotes an induction heating coil for test heating, which has a coil length such that, for example, one or two billets can be loaded side by side in the lengthwise direction. The induction heating coil 5 for test heating is provided below the heating coil 3 for normal heating in the lower half of the main body 1 in the illustrated example. As shown in FIG. 2, the induction heating coils 3 and 5 are connected to the power source 2 via a main circuit connector 6 and a switching disconnector 7, respectively.

The power supply 2 is equipped with a power supply unit for outputting low-frequency AC power to be supplied to the induction heating coil 3 and an opening / closing switch for turning on / off the output of power from the power supply unit, which are similar to the power supplies for known billet heaters.

In FIG. 2, reference numeral 8 is a capacitor.

In the above structure, during normal operation, the main circuit connector 6 is turned on, the switching disconnector 7 is turned off, heating power is applied to the induction heating coil 3, and the billet charged in the induction heating coil 3 is charged. Heating is performed.

On the other hand, when it is desired to heat a small number of billets on a trial basis, the billet is inserted into the induction heating coil 5, the switching disconnector 7 is turned on, the main circuit connector 6 is turned off, and a predetermined amount of power is induction-heated from the power source 2. Supply to the coil 5. As a result, the induction heating coil 5 heats a small number of billets charged in the heating coil 5.

The billet may be put in and taken out of the heating coil 5 manually or by moving a shaft movable in the axial direction of the heating coil.

Further, the heating temperature of the billet is controlled by bringing a temperature sensor into contact with the billet as used in a conventionally known billet heater, and by the output of the temperature sensor, the power source 2
It may be carried out by turning on / off a switch inside, and turning on / off the electric power applied to the heating coil 5.

Each of the induction heating coils 3 and 5 is made of a hollow conductor and is cooled by passing a coolant such as water through the hollow portion, similarly to the known ones. The water that passes through the heating coil 5 is obtained from a water supply system that supplies the induction heating coil 3.

Further, the induction heating coil 5 is provided with a support rail similar to that provided in a known induction heating coil for supporting the billet in a non-contact manner with respect to the heating coil.

Effects of the Invention As described in detail above, according to the present invention, in the billet heater, in addition to the heating coil for normal operation, a short induction heating coil having a short coil length for charging and heating a small number of billets and the induction heating. Since a switch for supplying power to the coil is provided, trial firing of a small number of billets can be performed efficiently and easily, and there is no need to install a heating device for trial firing, which is economical. .

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention, and FIG. 2 is an electric circuit diagram used in the apparatus of FIG. 1 ... Billet heater body, 2 ... Power supply, 3 ... Induction heating coil (for normal operation), 5 ... Induction heating coil (for testing), 6 ... Main circuit switch, 7 ... Switching disconnector.

Claims (1)

[Claims] 1. An induction heating coil (3) for normal operation, which is used during normal operation and has a coil length capable of loading a predetermined number of billets arranged in the longitudinal direction thereof, and the induction heating coil (3) for normal operation. A power supply (2) for supplying electric power to the and the induction heating coil (3) for normal operation are provided independently and used for test baking, and one or two billets are arranged in the longitudinal direction. An induction heating coil for test baking (5) having a coil length that can be loaded side by side, and a switch means (7) for supplying required power to the induction heating coil for test baking (5) are provided. A billet heater characterized in that.