JPS6012757B2 - High frequency heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-frequency heating device that includes a sealed heating chamber, a high-frequency oscillator, and a rotary shaft of a blower, etc., which is disposed through an opening provided in the metal heating chamber. In particular, it is equipped with a member used as a high frequency shield made of a metal disc, installed in the said barrier hole, located parallel to the heating chamber wall at a short distance, and connected to the said rotating shaft. This invention relates to a high frequency heating device.

A known example of such a high-frequency sealed high-frequency heating device is a metal disc that is located just outside an opening in the rotating shaft provided in the wall of the device and is attached to the rotating shaft of a blower.

This prevents high frequency waves from leaking from the heating chamber to the outside through the opening in the rotating shaft. A simple slot between the disc and the wall is completely immune to high frequency leakage.

Furthermore, the method in which a slot was provided between the disk and the surface of the wall was not particularly effective. These would be fine if the walls of the heating chamber were relatively cold, but the metal plates in the walls of the device would bend due to internal stress in the material due to exposure to high temperatures. The present invention is an attempt to improve these drawbacks, and its purpose is to prevent high frequency leakage without complicating the configuration of the device and without making it expensive.

The purpose of the high-frequency heating device of the present invention is to shield high-frequency waves leaking from the apertures and, in particular, to provide a circular slot connected to the high-frequency guide provided between the disk and the wall of the heating chamber.

In such a high-frequency heating device, the radial length of the high-frequency guide between the disk and the adjustable wall of the heating chamber and the length of the high-frequency trap are both suitably one-fourth of the wavelength of the high-frequency wave. .

Therefore, a ``high-frequency shield'' consisting of a high-frequency guide and a trap is installed at the location where high-frequency energy leaks from inside the heating chamber, and is installed in the barrier hole so that the rotation axis can rotate freely. This minimizes the leakage of high frequency leakage energy. The disc has a hub connected to the rotation axis, and a circular slot forming a high-frequency trap faces a hole located parallel to the direction of the rotation axis and opened opposite to the wall of the heating chamber. is the main part of the present invention. The high frequency trap is located on a portion of the blower wheel. It is provided on all blower wheels for normal heating operation. That is, it can be installed in the hub of the wheel without requiring special space. In another embodiment of the invention, the disc and the hub are fixed to a portion of the rotating shaft that projects inside the heating chamber.

Therefore, it is possible to compensate for the heating by a normal heater or the wall of the heating chamber where the heater and microwave oven are aligned, and it is also possible to prevent the disk or the wall from warping to one side, thereby partially increasing the space. can be suppressed. Another embodiment of the disc is to provide it in a radial gland plate of a hub that is fixed to the rotor of the blower.

The circular hub has a circular slot formed therein. It is also possible to install other shields.

External to blower motor. When a metal disc is fixed to the motor for heat conduction between the motor and the wall of the heating chamber,
The distance between the outside of the heating chamber and the cover plate will be equal to 1-2 sails. This forms a radio frequency shielding slot and is equal in length to approximately one quarter of the wavelength of the radio frequency.

This allows the heat-conducting disk to be covered with a ferrite material such as ferrite gum, which is best facing the wall of the heating chamber. In another embodiment of the invention, a metal lid is fixed to the outside of the wall of the heating chamber or to the cover plate of the stop.

The metal lid forms a circular slot between the inner surface of the disc and the outer surface of the wall, which acts as a radio frequency trap. Only the portion of the trap that is penetrated by the rotating shaft is mentioned. Specific embodiments of the present invention will be described below with reference to the drawings.

The figure is a rear view of the high-frequency heating device, and 1 is a cliff body surrounded horizontally, upwardly and downwardly by a heating chamber 2. A back plate 3 is inserted or welded to the oath body.

The back plate 3 is bent by several forces and has a beam flange 4, and the central closure 5 is covered from the inside of the heating chamber by a metal cover plate 6 between the border of the opening 5 and the metal cover plate 6. is a shield 7 formed by a conductive layer
is inserted. Said cover plate 6 has a central hole 8 through which the axis of rotation of the rotor 10 of the blower wheel with the external rotor 11 freely passes.

The blower 12 is fixed with a screw 13 to the end of the rotating shaft 9 of the blower motor 11 which projects into the heating chamber.
The blower wheel 12 has a radial gland plate 14 with a central hub 15;
has a central rotating portion 16 and a peripheral rotating portion facing the wall of the heating chamber. A rotary blade 18 of a blower is located around the ground plate 14. Blower wheel 1
A reflecting plate 2 is fixed to the bent portion 19 of the back plate 3, and this reflecting plate has a central hole 21 near a ventilation hole 22 for sucking air. The circular indicator in the figure was provided for high frequency shielding as described below. In other words, it is an obstruction to the leakage of high-frequency energy conversion from a high-frequency oscillator (not shown) through a high-frequency guide (not shown) in the heating chamber 2, and an obstruction to the leakage of the high-frequency energy from the high-frequency energy conversion through the barrier hole 8 of the back plate 3 to the outside. The high frequency guide 23 is a shielding material 7 inserted into the wall of the heating chamber.
and the internal rotating portion of the ground plate 14 of the blower wheel 12. This equals a distance between cover plate 6 and inner part 16 of approximately 1 to 1.5 skins. The hub 15 of the blower 12 is provided with a circular slot 24 parallel to the rotation axis. This slot is raised opposite the barrier hole 8 which forms the high frequency trap. The circular slot, the high frequency trap 24, and the high frequency guide 23 are also provided as high frequency shields. is 32 willow.Therefore, the aperture 8 is given as the minimum portion of the high frequency energy.

In the embodiment described above, the distance between the disk 16 and the inner surface of the cover plate is approximately equal to 1 to 1.5 feet. The clearance C of the high frequency trap in the circular slot 24 is about 7 ribs. As in the embodiments described above, the hub 15 has a separate part that projects through the aperture 8 in the cover plate 6.

Furthermore, a metal lid 26 is fixed to the outer surface of the cover plate. This is to make it resistant to temperature rises. This lid 26 is electrically connected to the cover plate 6 and also to the wall of the heating chamber. The circular indication part in the diagram is
The rotor 10 of the blower motor with an external rotor 11 can be fixed with a metal plate 28 to prevent heat transfer between the cover disk of the coupling hub 29 and the blower motor.

This metal plate 28 extends approximately 1 to 1 inch to the outer surface of the metal lid 26.
With just a distance of 5 fences. The radio frequency shielding slot has a radial length of a quarter wavelength of the radio frequency. The shielding effect is clearly demonstrated by experiments. The heat transfer of the disk 28 facing the wall of the heating chamber is performed using a ferrite material 3 such as ferrite rubber.
It is covered with 0. By providing a high-frequency shield around the opening 8 in this way, a blower can be installed, and the wheel 12 of the blower can be located separately inside the heating chamber 2, and is made of a reflector having ventilation holes 22. It can be placed in a space that is

It can also be used in normal open systems such as radiant heaters, and there is no need to pay attention to reflectors, and it has its own high-frequency shielding. Additionally, blowers can be used for multiple purposes. This is open as usual for heating such as electricity, radiation, and infrared radiation. The heat transfer prevention disc 28 serves to transfer the operating temperature of the blower motor 11, and the metal lid 26 serves to reduce the temperature.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a high-frequency heating device according to an embodiment of the present invention, and FIG. 2 is a plan view of a wheel seen from the motor side. 1...Lotus body, 2...Heating chamber, 3...
・Back plate, 4... flange, 5... opening hole,
6... Cover plate, 7... Shielding body, 8
......Central hole, 11...Motor, 12
...Wheel, 22...High frequency guide, 24...Slot, 26...Lid. Figure 1 Figure 2

Claims (1)

[Claims] 1. A heating chamber in which a high-frequency oscillator is provided, an opening provided in the wall of the heating chamber for passing a rotating shaft, and a hole connected to the rotating shaft and slightly connected to the wall of the heating chamber. a high frequency shield made of a metal plate located parallel to each other at a distance of A high-frequency heating device characterized by: 2. The high frequency heating device according to claim 1, wherein the slot forming the high frequency trap is provided in a hub connected to the rotating shaft. 3 The length of the above high frequency guide is 1/4 of the high frequency wavelength.
The high-frequency heating device according to claim 1, characterized in that: 4. The high frequency heating device according to claim 1, wherein the length of the slot provided in the hub connected to the rotating shaft is equal to one quarter of the wavelength of the high frequency. 5 A motor is provided on a portion of the rotating shaft that protrudes outward from the heating chamber, a rotor blade is provided on a portion of the rotating shaft that protrudes inward of the heating chamber, and a rotor is provided inside the heating chamber. 2. The high-frequency heating device according to claim 1, wherein the rotary blade body is substantially covered and air holes are provided in a portion thereof. 6. Claim 1, characterized in that a cover plate is provided around the rotating shaft to cover the opening, and a ferrite material is interposed at the joint between the cover plate and the wall of the heating chamber. high frequency heating device. 7. The high-frequency heating device according to claim 5, further comprising a heat insulating plate positioned between the motor and the outer wall of the heating chamber around the rotating shaft.