JPS6323869Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] This invention relates to a magnetron device in which an external inductor element is connected to the magnetron to suppress high frequency band noise propagating from the cathode terminal side of the magnetron to the power supply lead wire. .

[Technical background of the idea]

Generally, magnetrons are widely used in microwave ovens and the like. The oscillation frequency of this type of magnetron is, for example, 2450 MHz, but from the cathode stem side, radio noise called unnecessary radiation is generated from the medium wave band to the high frequency band, superimposed on this frequency.

Therefore, on the cathode stem side, an LC filter consisting of a choke coil and a capacitor is placed in a shield box to suppress noise in the high frequency band and harmonic band. However, although the choke coil is effective against high-frequency noise, if the inductance is not set to an appropriate value, it may cause choke burnout and adversely affect the characteristics of the magnetron, and there are also structural limitations due to the fact that it is inside a shield box. , has a limiting factor. Therefore, depending on the operating conditions of the magnetron in the microwave oven, the suppressing power of unnecessary radiation may be insufficient and a new unnecessary radiation suppressing element may be required between the magnetron and the power supply. An external inductor element made of a choke coil is used for the band. This type of external inductor element has conventionally been described in, for example, Japanese Unexamined Utility Model Publication No. 10211/1982 and Japanese Utility Model Publication No. 52658/1983.

[Problems with background technology]

The conventional external inductor element described above is connected between the magnetron and the power source, but has the following drawbacks.

Because it comes with a lead wire, it is inconvenient to handle and has poor workability.

It is mechanically suspended when connected between the magnetron's cathode terminal and the power supply, and is unstable due to vibrations during transportation of the microwave oven.

Depending on the arrangement of parts in the power supply room of the microwave oven,
It tends to be adjacent to other high-voltage parts or heat-generating parts, which is not desirable from a safety standpoint.

It is difficult to say that the mechanical strength is sufficient.

[Purpose of invention]

The object of this invention is to provide a magnetron device having an external inductor element that can sufficiently suppress high frequency band noise, is small, and can be reliably and easily installed.

[Summary of the idea]

In this invention, an L-shaped or Z-shaped external inductor element is connected and fixed to the input end of the magnetron so that the internal choke coil is parallel to the tube axis of the magnetron.

[Example of idea]

The magnetron device of this invention is constructed as shown in FIG. 1, where 1 is the main body of the oscillating section. That is, a plurality of vanes 3 are arranged radially inside the anode cylinder 2, and every other vane is connected by a strap ring 4. Further, substantially funnel-shaped pole pieces 5 and 6 are fixed to both ends of the anode cylinder 2, and one pole piece 5 has a cathode stem 7, and the other pole piece 6 has a cathode stem 7. Output sections 8 are provided in a protruding manner. Further, a directly heated electron emitting cathode 9 is arranged spirally along the axis of the anode cylinder 2, and is supported by cathode supports 10 and 11. The cathode supports 10 and 11 are connected to cathode terminals 12 and 13 forming the cathode stem 7. An antenna feeder 14 is fixed to one of the vanes 3, and this antenna feeder 14 is located within the output section 8. And on both sides of the oscillating unit main body 1,
Permanent magnets 15 and 16 are disposed to surround a portion of the cathode stem 7 and a portion of the output section 8, respectively. Further, on the outer periphery of the anode cylinder 2, a radiator 17 consisting of a plurality of fins is provided. A frame-like yoke 18 surrounds the radiator 17, the oscillating unit main body 1, and the permanent magnets 15 and 16.
is arranged and is in contact with both permanent magnets 15 and 16. Furthermore, a shield box 19 is arranged to surround the cathode stem 7 and is in contact with the yoke 18. Inside this shield box 18 is a choke coil 20 connected to the cathode terminals 12 and 13.
Further, this choke coil 20 is provided with a feedthrough capacitor 2 fixed to the wall of the shield box.
1 is connected. The outer terminal 50 of this feedthrough capacitor 21 also serves as the input terminal of the magnetron, and an L-shaped external inductor element 22 , which is a feature of this invention, is connected to the outer side of the terminal 50.

This generally L-shaped external inductor element
6 is a perspective view of the exterior, FIG. 3 is a plan view of the interior, and FIGS. 4 and 5 are perspective views of the container body and the container cover.
FIG. 6 is a perspective view showing the vicinity of the built-in choke coil. That is, as shown in the figure, a container cover 24 is removably connected to a container body 23 to form an insulating container, but the container body 23 is generally L-shaped as is clear from FIGS. 2 and 4. It has a frame-shaped recess 25 at one end into which the external terminal portion of the feedthrough capacitor 21 of the magnetron is inserted, and a pair of tab positioning grooves 26 and 27 at the other end. In addition, a partition wall 28 and fixing screw holes 29 are integrally provided in the center of the interior, and a pair of receptacle insertion holes 30 and 31 that are opened in the recess 25 are bored on one side, that is, on the recess 25 side. ,
On the other side, that is, on the tab positioning grooves 26 and 27 side, a pair of tab insertion grooves 32 and 33 are provided. Further, a stopper 34 is provided in the recess 25 in a protruding manner as shown in FIG. Furthermore, the container cover
24 corresponds to the container body 23 as shown in FIG. 5, and a partition wall 35 and fixing screw holes 36 are integrally provided in the center of the interior, and a receptacle holder 37 is protruded from one side. A pair of tab positioning grooves 38, 39 and tab insertion grooves 40, 41 are provided on the other side. In addition, the main body 2
3 and the container cover 24 are both made of an insulating material such as styrene-grafted polyphenylene ether resin.

Now, on both sides of the partition wall 28 inside the container body 23, as shown in FIG. Although it is established,
As shown in FIG. 6, this choke coil 44,
One end of each of the tabs 45 is connected to the receptacles 46 and 47 by caulking or welding, and the other end is electrically and mechanically connected to the back surfaces of tabs 48 and 49 bent into an L shape by welding. The receptacles 46 and 47 are inserted into the receptacle insertion holes 30 and 31, respectively, and the tabs 48 and 49 are tightly fitted into the tab positioning grooves 26 and 27, respectively, and the bent tips 48a and 49a are used for tab insertion. It is inserted and fixed into the cut grooves 32 and 33. after that,
If you align the container cover 24 with the container body 23 and insert screws into the fixing screw holes 29 and 36 to connect them, the L
A letter-shaped external inductor element 22 is completed. At this time, the tab positioning grooves 38 and 39 of the container cover 23
And the notch grooves 40 and 41 for tab insertion are tabs 49,
48 and bent portions 49a, 48a, and the receptacle presser 37 contacts the receptacles 46, 47.

This external inductor element 22 is attached to the magnetron as shown in FIG. (although only two are visible, there are actually two) are inserted and connected to the receptacles 47 and 46. In other words, the external inductor element 22 can be attached to the magnetron in a so-called one-touch operation. Note that the outer wall 22a of the external inductor element 22 is separated from the shield box 19. Further, the tabs 48 and 49 are connected to a power transformer 51 in the microwave oven when in use. Furthermore, as is clear from FIG. 1, the choke coil 4 of the external inductor element 22
4 and 45 are constructed so as to be parallel to the tube axis C-C' of the magnetron, which is a feature of this invention. Incidentally, the choke coil is not limited to one having a core, but may be one having an air core, or one in which a core shape and an air core shape are integrated. In addition, since the outer end shape of the tab 49 is the same as the outer terminal 50 of the feedthrough capacitor which also serves as the magnetron input terminal, it is possible to connect the tab 49 via this external inductor element without replacing any connectors on the power supply side. Connectable and compatible. Furthermore, the shortest spatial distance l from the shield box to the tab of the external inductor element should be 10 mm or more or 15.5 mm based on the standard.
[Effect of the invention] As set above, since the external inductor element 22 is connected between the magnetron and the power source, high frequency band noise can be sufficiently suppressed as desired.

The external inductor element 22 is a so-called package.
Since it is a double type and compact, it is convenient to handle, and since the longitudinal direction of the choke coil is parallel to the magnetron axis, the entire device is compact.

The external inductor element 22 can be attached to and detached from the magnetron with a single touch, which provides good operability and ensures reliable and stable operation.

Since the container of the external inductor element 22 is made of an insulating material such as styrene-grafted polyphenylene ether resin, it has high safety properties such as pressure resistance and heat resistance.

In the above embodiment, the external inductor element 22 was L-shaped, but as shown in FIG.
Even if a letter-shaped external inductor element 52 is used, the same effect as in the above embodiment can be obtained. In this case, tab 4
The portion 52a on the 9 side is formed in the same shape as the outside of the feedthrough capacitor 21. As a method of attaching this external inductor element 52 to the magnetron, the eighth
There are two possible types as shown in Figs. do not have. This allows the entire magnetron device to be relatively compact and mechanically stable.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a magnetron device according to an embodiment of this invention, FIG. 2 is a perspective view showing the external appearance of an L-shaped external inductor element used in the magnetron device of this invention, and FIG. 3 is a similar view. 4 and 5 are perspective views showing the container body and the container cover, and FIG. 6 is a plan view showing the inside.
Figure 7 is a side view showing a Z-type external inductor element which is a modification of this invention, Figures 8 and 9 are the Z-type external inductance element of Figure 7. FIG. 3 is a side view showing two examples of how to attach the magnetron to the magnetron. C-C'...Magnetron tube shaft, 21...Feedthrough capacitor, 22 ...L-shaped external inductor element,
23... Container body, 24... Container cover, 25...
... recess, 26, 27, 38, 39 ... tab positioning groove, 28, 35 ... partition wall, 30, 31 ...
Receptacle insertion hole, 32, 33, 40, 41
... Notch groove for tab insertion, 42, 43 ... Ferrite core, 44, 45 ... Choke coil, 4
6, 47... receptacle, 48, 49... tab.

Claims (1)

[Claims for Utility Model Registration] A pair of external terminals 5 of the feedthrough capacitor 21
0 exposed to the outside from the shield box 19; an external inductor element 22 connected in series between the capacitor external terminal 50 of the magnetron and the power supply circuit device 51;
52, the external inductor elements 22 , 52 are comprised of an approximately L-shaped or Z-shaped insulating container 23, 24, and a pair of rod-shaped tubes housed within the insulating container. Kucoil 4
4, 45, and a pair of receptacles 46, 4 fixed to one end of the insulating container, electrically connected to each of the choke coils, and having a shape and size such that the capacitor external terminal 50 is tightly inserted.
7, and a pair of tabs 48 and 49 fixed to the other end of the insulating container, electrically connected to the other end of each of the choke coils, and having end shapes and dimensions similar to the capacitor external terminals. A magnetron device, characterized in that the rod-shaped choke coils 44, 45 are detachably connected between the magnetron and a power circuit device in parallel to the tube axis C-C' of the magnetron.