JPH046155Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The invention is an induction heating device that induction heats a workpiece for the purpose of hardening, tempering, etc. The present invention relates to a multi-coil type induction heating device including a plurality of heating coils each having a different shape.

(Prior Art) In some cases, an induction heating device equipped with a power source having a predetermined frequency and output is equipped with a plurality of heating coils each having a different shape in a heating station.

That is, a plurality of different types of workpieces with different sizes and shapes are fed randomly or in small lots, but as long as the heating coils are replaced with ones that are shaped to suit the different types of workpieces,
In order to respond immediately when appropriate heating can be achieved under nearly identical matching conditions, the heating station is equipped with heating coils that have different shapes to match the shapes of different types of workpieces that are scheduled to be fed into the heating station. The type of work being fed is identified using, for example, a shape discrimination sensor, and the corresponding heating coil is selected and used accordingly.

FIG. 3 shows a structure for selectively using heating coils in this kind of induction heating device equipped with multiple coils.

In the figure, E is a power source, T' is a matching transformer with a predetermined turns ratio, HS is a heating station, C1 to C3 are heating coils placed in the heating station HS, K is a pedestal, and S is a switch.

The transformer T' has output terminals a, which extend from a secondary side opposite to a primary side connected to the power source E.
b is set to be located near the fixed heating position of the heating station HS.

The heating coils C1 to C3 have different heating conductor winding diameters, widths, or number of turns, for example.
A lead portion indicated as R is fixedly arranged on the mount K, and the tips of the lead portion R extended by a predetermined length serve as input terminals c and d.

The gantry K is configured to be movable in the left and right directions as shown by arrows.

Therefore, if the extension length of the lead portion R of each of the heating coils C1 to C3 is set to a predetermined value, the transformer can be heated by moving the frame K by a predetermined amount in the left and right direction.
The output terminals a, b of T' are opposed to the input terminals c, d of a desired heating coil among the heating coils C1 to C3, for example, C2, and in this state, the switch S
By operating the heating coil C2.
A circuit can be closed between the power source E and the workpiece can be heated by the heating coil C2.

(Problems existing in the prior art) By the way, induction heating devices usually use a large current, but in order to use the selected heating coil C, the output terminals a, b of the transformer T' and the heating coil C1
In the multi-coil induction heating device having the above configuration, which is based on the premise of frequent switching between the input terminals c and d of C3, the contact portions are subject to extremely severe wear and tear due to arc flaws and the like that occur during switching.

For example, when using a 30-40KHz, 150Kw oscillator as a power source, the contact part
A current of 5,000 to 15,000 A flows, and the arc generated is large and intense.

If a contact part becomes worn out, the operation of the induction heating device must be stopped and the relevant part must be replaced with a new one, which reduces productivity and increases repair costs.Therefore, countermeasures have been desired.

(Purpose of the invention) The present invention solves the above-mentioned problems with conventional induction heating devices that have multiple heating coils of different shapes in the heating station and use different heating coils depending on the shape and dimensions of the work being fed. The purpose of this invention is to provide an induction heating device equipped with multiple coils, which eliminates the need to stop operation of the induction heating device due to wear and tear on the contact portions.

(Structure of the invention) The gist of the invention is as follows: (1) In order to process multiple types of workpieces that can be heated under almost the same matching conditions, a heating station is equipped with multiple heating coils of different shapes, and the workpieces are fed. In an induction heating device in which heating coils are selected and used depending on the type of (3) The secondary elements are formed to have the same structure with the inner diameter of the wound conductor being slightly larger than the outer diameter of the wound conductor of the primary element, and (4) the secondary elements are (5) A desired one of the secondary elements and the primary element are configured to be able to face each other by relative movement, (6) The primary element and the secondary element occupy opposing positions. A side element forms a transformer, and a heating coil fixed to the secondary side element is set to perform heating.

(Function of the invention) This invention forms a transformer by combining the secondary element and the primary element, to which the heating coil of the selected and used shape is fixed, by relative movement, so there are no contact points. It has an effect.

(Example 1) The present invention will be described in detail below according to a first example shown in FIGS. 1a and 1b.

In the figure, E is a power source, 1 is a primary side element connected via a circuit 11 such as a bus bar, and has a predetermined number of conductor turns and a winding diameter as an element forming a transformer together with a secondary side, which will be described later. ~2c is 3
C1 to C3 are the secondary elements 2a to 2a, which are arranged in a row at predetermined intervals on the table shown as , and are composed of wound conductors that form a transformer together with the primary element. 2c is a heating coil fixed to each via a lead R.

Circuit 1 connecting the above power source E and primary side element 1
1 is set so that the part in the direction of the primary side element is a straight part, and the length of the straight part is at least equal to or longer than the length of the row of secondary elements 2a to 2c arranged on the table 3. There is.

In this embodiment, the primary element 1 is fixed to an immovable circuit 11, and has its wound end face oriented in the left-right direction.

Each of the secondary elements 2a to 2c is formed in the same structure so that the inner diameter of the conductor winding is slightly larger than the outer diameter of the conductor winding of the primary element 1. Further, each of the secondary side elements 2a to 2c is arranged on the table 3 so that the winding end face is oriented in the left-right direction, and the winding axis coincides with an extension of the winding axis of the primary side element 1.

The heating coils C1 to C3 have different shapes as shown in the figure, and are formed to match the shapes and dimensions of a plurality of different types of workpieces W to be heated.

The table 3 is formed so as to be movable in the left-right direction parallel to the straight portion of the circuit 11 according to the arrows shown in the figure.

Therefore, if the table 3 is moved sufficiently, for example, to the right, the table 3 will move as shown in FIG. 1a.
The secondary element 2a placed above is located on the outer periphery of the primary element 1 which maintains a fixed state, and an electromagnetic coupling state occurs between the primary element 1 and the secondary element 2a facing each other, and the transformer T1 It is formed. Furthermore, if the table 3 is moved a predetermined amount to the left from the above state, the first
As shown in Figure b, the secondary element 2b placed on the table 3 is located on the outer periphery of the primary element 1,
An electromagnetic coupling state occurs between the primary side element 1 and the secondary side element 2b facing each other to form a transformer T2. Transformer T3 can also be formed in a similar manner.

As described above, the present invention can automatically form the transformers T1 to T3 individually by moving the table 3, and connect the heating coils C1 to C3 and the power source E without switching the contacts as in the conventional induction heating device. The circuit can be closed individually.

(Example 2) FIG. 2 shows a second embodiment of the invention.

In the figure, E is a power source, 1 is a primary side element connected to the power source E, and 2a to 2c are secondary side elements arranged at a predetermined interval on a table 3 that can be moved in the left and right direction as shown by the arrow. The above secondary element 2a~
2c each has a different shaped heating coil C1~
C3 is attached, but in this figure showing a front cross-section, the heating coils C1 to C3 are located toward the front via the lead R, and therefore cannot be seen. The second embodiment is different from the first embodiment in that the winding axes of the primary element 1 and the secondary elements 2a to 2c are in the vertical direction, and the primary element 1 is It is connected to a power source E via a circuit 12 made of a flexible conductor, and an electrical insulating material 4 is fixed to the upper end surface, and a rod 5 of a vertical displacement mechanism (not shown) is connected to the upper surface of the electrical insulating material 4. The primary element 1 is configured to be able to be displaced upward or downward by driving a vertical displacement mechanism.

Therefore, when selecting and using a desired heating coil C, the primary element 1 is first displaced upward, and the heating coil C is fixed by moving the table 3 by a predetermined amount in either the left or right direction. The secondary element 2 may be positioned directly below the primary element 1, and the primary element 1 may be displaced downward.

It goes without saying that the second embodiment also exhibits exactly the same functions and effects as the first embodiment.

(Other Embodiments) As a modification of the second embodiment, a plurality of secondary elements 2 may be arranged on the periphery of the rotary table, and heating coils C fixed to each may be protruded to the outside of the periphery. .

(Effects of the invention) By implementing this invention, there is no need to stop operation of induction heating equipment due to wear and tear of the contact parts, greatly improving productivity, and reducing costs by eliminating expenses for repairing the contact parts. The effect it brings is enormous.

[Brief explanation of the drawing]

Figures 1a and b are cross-sectional plan views showing the first embodiment of the present invention, Figure 2 is a cross-sectional front view showing the second embodiment of the present invention, and Figure 3 is a plan view showing the conventional example. It is. C1-C3... Heating coil, W... Workpiece, E
...Power source, T, T1-T3...Transformer, 1...Primary side element, 2, 2a-2c...Secondary side element.

Claims (1)

[Scope of utility model registration request] In order to process multiple types of workpieces that can be heated under almost the same matching conditions, the heating station is equipped with multiple heating coils with different shapes, and the heating coils are selected and used depending on the type of workpiece being fed. In the induction heating device, the matching transformer to be arranged is divided into one primary element connected to the power supply and a plurality of secondary elements, and the secondary element has the inner diameter of the wound conductor connected to the primary side. The elements are formed to have the same structure with the same dimensions slightly larger than the outer diameter of the wound conductor, and the heating coil is fixed to each of the secondary elements, and a desired one of the secondary elements and the primary element are connected to each other. are configured so that they can face each other by relative movement, and the primary and secondary elements occupying opposing positions form a transformer, and the heating coil fixed to the secondary element performs heating. This is an induction heating device equipped with multiple coils.