JPS60175390A - Heating temperature distribution regulator for ac field induction heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for uniformly adjusting the distribution of heating temperature in a cross-magnetic field type induction heater, and relates to a device for uniformly adjusting the distribution of heating temperature in a cross-magnetic field type induction heater. Related to IM (filed on November 50, 1995).

Conventionally, as this type of cross-magnetic field type induction heater, the one shown in FIG. 1 has been generally used.
A'8 yohi 2B?] Paired on the plate. The heaters 2A and 2B each have coils 3A and 3B wound around each magnetic pole (pole) 4U, and this coil 3A
, 3B, an alternating magnetic field is generated from each magnetic pole. When the heated object 1 is placed within this alternating magnetic field, eddy currents flow through the heated object due to electromagnetic induction.

Joule heat is generated by this eddy current, and the object to be heated itself is heated.

Such a cross-magnetic-field five-induction heater has a drawback in that the ends and center of the object to be heated are not uniformly heated because an etch effect occurs during heating. That is, as shown by the solid line in FIG. 1, the width of the dielectric of heaters 2A and 2B, that is, the width v4 of heater 2
When an object to be heated 1 having a width smaller than the width substantially equal to W is heated, its edges are heated more than the center, while the width is smaller than the width substantially equal to W. In the case of a large object to be heated IA, there is a problem in that the ends of the object cannot be sufficiently heated compared to the center.

The edge effect described above relates to the width direction of the object to be heated, but the same etch effect also occurs in the vertical direction. In other words, if the vertical width of the object to be heated is smaller than the magnetic pole spacing (distance between the N-pole ball and the S-pole ball) of 1 inductor, the end of the object will be overheated, and if it is larger, the end of the object will be overheated. There was an inconvenience that this was insufficient. The invention related to the prior order of the present applicant described above uses a magnetic material with low magnetic resistance to enhance the magnetic flux generated from the inductor, thereby improving or eliminating the non-uniformity of heating temperature property 41 caused by the edge effect. This is what I am trying to do.

The present invention solves the uneven heating temperature distribution caused by such an etch effect by using a non-magnetic conductor with high magnetic resistance to reduce the magnetic flux generated from the inductor.
The present invention provides an adjustment device that seeks to improve or eliminate the problem.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In the cross-magnetic field type induction heater shown in No. 214, the same or equivalent members as those shown in FIG. 1 are given the same reference numerals 1 as in FIG. 1, and the explanation thereof will be omitted. The object to be heated IA with a small width dimension is the heater 2A, 2B.
When placed in between, in order to avoid non-uniformity of temperature 41 due to the edge effect described above, that is, overheating of the edges relative to the center, a rectangular parallelepiped shaped like the one shown in FIG. 3 is cut along the diagonal of the side surface. For example, a non-magnetic conductor core 4 made of aluminum or copper is covered with a hot material L as shown in FIG.
Place 4 pieces (4A, 4A', 4B, 4B') at the end of A. The two cores shown as 4A and 4A' form a set with A! at both ends. be placed. The presence of the core made of a non-magnetic conductor increases the magnetic resistance of the magnetic flux passing through it, resulting in a decrease in magnetic flux density. That is, since the magnetic flux energy passing through the non-magnetic conductor is consumed as thermal energy due to overcurrent, the non-magnetic conductor functions to reduce the passage of magnetic flux. Therefore, the ends of the object to be heated IA are heated more weakly than in the case where there is no core, and therefore it is possible to heat the object IA almost uniformly with the center. Note that it is desirable to be able to adjust the position of the core in accordance with the width W of the object to be heated, and for this purpose, for example, screw means or cam means (not shown) can be used.

Referring to FIG. 4, the manner in which the cores are arranged in the vertical direction becomes clear. That is, three cores 48-1, 4A-2
, 4A-3 are magnetic poles N and S arranged at a ball pitch of 2P.
, N are arranged at the same intervals. Since FIG. 4 shows only the upper heater 2A and omits the illustration of the lower heater, in the embodiment shown in FIG.
A total of 12 cores are used, including 6 cores for A and 6 for the side heater 2B. As shown in Figure 4, cores 4A-1, 4A-2
, 4A-3 is placed directly under each magnetic pole, the magnetic flux density from the magnetic poles is reduced by -C by the core as described above,
Heating of the object near the core is reduced. On the other hand, if we move the cores in Figure 4 to the positions shown in Figure 5, that is, when each core is located between the magnetic poles, the magnetic flux from each magnetic pole passes through the core with large magnetic resistance. Because of this difficulty, the magnetic flux from the magnetic poles is not blocked, thus increasing the heat generated. The cores of each set can be integrally moved from the position shown in FIG. 4 to the position shown in FIG. 5, and by adjusting the amount of movement, the heating of the heated object IA is continuously adjusted from weak to strong. becomes possible. As a means for integrally moving these plurality of cores, as shown in FIG. It is possible to move it using suitable eg cam means or screw means (not shown).

As mentioned above, when the width W' of the object to be heated is narrow, the cores 44A, 4B
, 4A', and 4B' as shown in FIG. 2, and in the longitudinal direction at a position directly below or close to the magnetic pole as shown in FIG. It is possible to prevent overheating and reduce unevenness with respect to the center. On the other hand, when the width W' of the object to be heated is large, the edges are less likely to be heated than the center due to the edge effect. By placing the arrangement between the magnetic poles as shown in Figure i5, or at a position close to them, it is possible to enhance the heating at the ends and avoid non-uniformity with the center.

In the embodiments described above, the shape of the core was explained as shown in FIG. 3, but the present invention is not limited to this shape, and the slope shown in FIG. 3 may be curved, for example, instead of straight. But there's no problem.

In other words, it is sufficient that the heater has a shape in which the thickness gradually increases toward the ends in the width direction of the heater, and the vertical width is approximately equal to the vertical width a of the magnetic pole. Furthermore, although a pair of heaters is shown in the embodiment, the desired effect of the present invention can be achieved with either one of the heaters.

Furthermore, in the embodiment shown in FIG.
``, 4E''Drawings for each group''-person, I mentioned the case where it is installed on the right.

The present invention is not limited thereto; for example, the upper cores 4A and 4A' may be arranged on the right and left, respectively, or even if only the lower cores 4B and 4B' are arranged on the right and left, respectively. The intended objects and effects of the invention can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a conventional cross-magnetic field type heater, Fig. 2 is a front view showing an embodiment of the present invention, Fig. 3 is a side view showing a non-magnetic conductive core, and Fig. 4 is a front view showing a conventional cross-magnetic field type heater. , FIG. 5 is a side view showing the arrangement relationship between the magnetic poles and the non-magnetic conductive core in the embodiment. 1.IA 3. , , Objects to be heated 2A, 2B, , Heaters 3A, 3B, , Coils 4.4A, 4B, , Non-magnetic conductor core. 5, , , , , , plastic member S, N , ,
,,,,Magnetic Pole 2F,,,,,,,,, Paul Pitch, Patent Attorney, Takeo Goto, Patent Attorney, Isao Fujimoto Figure 1

Claims (1)

[Claims] 1. A cross-magnetic field type induction heater and a plurality of non-magnetic conductive cores disposed between the object to be heated by the cross-magnetic field type induction heater and the cores of the heater. The cores are arranged at one or both ends in the width direction to correspond to each of the plurality of magnetic poles arranged in the vertical direction of the heater, and the plurality of cores can be integrally moved in the vertical direction. J! so that the heating temperature distribution of the object to be heated becomes uniform. A device for adjusting the heating temperature distribution of a cross magnetic field 2 (1ν induction heater), characterized in that the cross magnetic field 2 (1ν) can be adjusted. 2.4. The shape of the body core is such that the thickness gradually increases in the width direction of the heater toward the end thereof, and has a width in the longitudinal direction that is approximately equal to the longitudinal width of the magnetic pole. Heating temperature tri of magnetic field type induction heater, A adjustment device.