JPH071846Y2 - Dielectric resonator mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention has a dielectric resonator having an upper plate, a lower plate and a side plate, and a columnar dielectric member fixed between the upper plate and the lower plate. The present invention relates to a structure for attaching to a bottom portion of an outer case having an open top surface.

[Conventional technology]

Conventionally, as a dielectric resonator utilizing the resonance of the TM mode system, as shown in FIG. 4, an upper plate 20, a lower plate 21, and a side plate 22,
It is known that a case is constituted by 23 and a columnar dielectric 24 is fixed between the upper plate 20 and the lower plate 21. In addition, the upper plate 20,
The lower plate 21 and the side plates 22 and 23 are formed of a dielectric similar to the columnar dielectric 24, and a conductive film 25 is formed on the inner surface thereof.

When a filter is formed using the resonators having the above structure, it is necessary to fix each resonator to the metal outer case 26 or the like. Therefore, conventionally, a hole 27 is formed in the lower plate 21,
A silver-plated cap screw 28 is fitted into this hole 27 and temporarily fixed in advance, a screw insertion hole 29 is formed in the outer case 26, and a fixing screw 30 is screwed into the outer case 26 from the lower side.
The resonator is fixed to the outer case 26 by being screwed onto the cap screw 28 via the.

[Problems to be solved by the device]

However, in the case of the above fixing method, the outer case 26
There is a problem that the workability is extremely poor because the fixing screw 30 is inserted from the lower side and the screwing work is performed while holding the resonator so as not to be displaced with respect to the outer case 26. Also, plated cap screws 28
There is also a problem in that cost is increased because special parts that are not commercially available are required.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a mounting structure for a dielectric resonator which is excellent in mounting workability when mounted on an outer case and is inexpensive.

[Means for Solving the Problems]

According to the present invention, a dielectric resonator having an upper plate, a lower plate and a side plate, in which a columnar dielectric is fixed between the upper plate and the lower plate, is attached to at least a bottom portion of an outer case having an open top surface. In the structure for, a tool insertion hole formed in the upper plate,
A screw insertion hole formed at a position corresponding to the tool insertion hole of the lower plate, and the screw insertion hole is inserted with the head on the upper side,
A fixing screw whose head is rotated by a tool inserted into the tool insertion hole, an elastic retaining ring fitted to a downward projecting portion of the fixing screw, and the dielectric resonator The above object is achieved by including a screw hole formed in the bottom portion of the outer case that supports the lower plate and into which the protruding portion of the fixing screw is screwed.

[Action]

That is, by inserting the fixing screw into the screw insertion hole of the lower plate in advance and holding the downward projecting portion by the retaining ring, the fixing screw is integrated without dropping from the dielectric resonator. It can be handled. Moreover, since the screw insertion hole of the lower plate and the tool insertion hole of the upper plate correspond to the upper and lower sides, place the dielectric resonator inside the outer case and insert a tool such as a screwdriver from above. If the fixing screw is operated, the work can be performed from above the outer case, and the fixing screw and the dielectric resonator can be easily screwed without holding each.

〔Example〕

1 to 3 show a dielectric resonator A using TM ₀₁₀ mode.
An example is shown, which includes a cylindrical dielectric 1, a square upper plate 2, a lower plate 3 and two side plates 4 and 5 which form a case. In this embodiment, two opposite front and rear surfaces of the case are open, and a multistage filter can be configured by connecting a plurality of resonators to each other at the open portions.

The upper and lower plates 2 and 3 and the side plates 4 and 5 are made of, for example, the same material as the columnar dielectric 1, that is, a dielectric plate, and the conductive film 6 is formed by applying a silver paste on the entire inner surface and baking it. Has been formed. The inner surfaces of the upper and lower plates 2 and 3 on which the conductive film 6 is formed are fixed to the upper and lower end surfaces of the cylindrical dielectric 1 with a bonding material such as silver paste or solder.

The conductive film 6 provided on the upper and lower plates 2 and 3 and the side plates 4 and 5 may be provided on the outer surface instead of the inner surface. At this time, the cylindrical dielectric 1 and the upper and lower plates 2 and 3 do not flow even if they are connected by silver, so it is necessary to connect them by glaze. Further, the conductive film 6 may be provided on the entire inner and outer surfaces. In any case, the conductive film 6
Surrounds the columnar dielectric 1 and has a function as a conductive path and a shield function. Although the upper and lower plates 2 and 3 and the side plates 4 and 5 constituting the case may be made of a metal material as described above, it is better to be made of the same material as the cylindrical dielectric 1 as described above. There is an advantage that excellent temperature characteristics can be obtained.

Four tool insertion holes 7 are formed near the four corners of the upper plate 2, and the insertion holes 7 have a diameter such that a rotary tool 8 such as a screw driver can be inserted as shown in FIG. ing. Further, four screw insertion holes 9 are formed at positions corresponding to the tool insertion holes 7 of the lower plate 3, and a metal flat washer 11 and a spring washer 12 are provided in the screw insertion holes 9. The fixing screw 10 passed through is inserted with the head 10a thereof facing the upper plate 2 side, and the protruding portion protruding downward has a flexible elasticity such as tetrafluoroethylene resin as shown in FIG. ring
13 is press-fitted. Therefore, the fixing screw 10 does not fall off from the lower plate 3 even when the resonator A is turned upside down. Since the fixing screw 10, the flat washer 11, and the spring washer 12 are all made of a metal material, they function as a shield together with the conductive film 6, and the leakage of electromagnetic waves from the screw insertion hole 9 of the lower plate 3 is prevented.

In the above embodiment, since the tool insertion hole 7 of the upper plate 2 and the screw insertion hole 9 of the lower plate 3 are formed with the same diameter, it is possible to use the resonator A upside down, and the directional characteristic Can be eliminated.

The outer case 14 is formed by three metal plates and has a U-shaped cross section, and a screw hole 15 is formed at a position corresponding to the screw insertion hole 9 at the bottom thereof. Also, the outer case 14
As shown in FIG. 1, a spacer 16 of the same material and the same thickness as the ring 13 is arranged on the bottom surface of the bottom of the spacer 16 and four openings 16a are formed in the spacer 16 so as not to interfere with the ring 13. Has been done. The protruding portion of the fixing screw 10 is screwed into the screw hole 15 of the outer case 14, and the spacer 16 is sandwiched between the bottom portion of the outer case 14 and the lower plate 3 of the resonator A. The cushioning properties of the spacer 16 and the ring 13 reduce the vibration and impact force applied to the outer case 14 so as not to be directly transmitted to the internal resonator A.

If the ring 13 and the spacer 16 are made of one sheet and are attached to the bottom surface of the lower plate 3 together with the fixing screw 10, the spacer 16 having the opening 16a as shown in FIG. 1 becomes unnecessary, and the structure is simplified. Become.

Next, a method of fixing the dielectric resonator A having the above structure to the outer case 14 will be described.

First, the fixing screw 10 is attached to the lower plate 3 of the resonator A in advance by the ring 13. Then, the resonator A is housed in the outer case 14 in which the spacer 16 is arranged, and the protruding portion of the fixing screw 10 is aligned with the screw hole 15 of the outer case 14. Then, the rotary tool 8 is inserted into the tool insertion hole 7 from above, the tip of the tool 8 is engaged with the head 10a of the fixing screw 10, and the fixing screw 1
The resonator A is fixed to the outer case 14 by screwing 0 into the screw hole 15. After that, by assembling the lid 17 shown by the alternate long and short dash line in FIG. The tool insertion hole 7 formed in the upper plate 2 may be closed by a shield member, but in the case of this type of dielectric resonator, the electromagnetic wave leaks little, so the shield member is not essential.

As described above, the resonator A can be fixed to the outer case 14 simply by placing the resonator A inside the outer case 14, inserting the rotary tool 8 from above and rotating the same. Since it can be screwed, the workability is far better than in the past and the burden on the operator can be reduced.

Further, when the fixing screw 10 is screwed, the tightening force of the fixing screw 10 is absorbed by the cushioning properties of the spring washer 12, the ring 13 and the spacer 16. Therefore, even if the fixing screw 10 is tightened too much, the lower plate 3 is excessively tightened. The load is not concentrated and the lower plate 3 made of a dielectric material can be prevented from cracking or breaking.

In the above embodiment, the case where the screw hole 15 is formed in the outer case 14 is shown, but a screw insertion hole may be provided in the outer case, and a nut screwed with the fixing screw may be arranged outside the outer case.

Further, the present invention is not limited to the TM mode type dielectric resonator using the columnar dielectric, but can be applied to other types of dielectric resonators, for example, TE ₀₁ mode dielectric resonators.

[Effect of device]

As is clear from the above description, according to the present invention, the fixing screw is inserted into the screw insertion hole of the lower plate, and the downward protruding portion is held by the retaining ring so that the fixing screw is It can be handled integrally without dropping from the body resonator. Moreover, since the screw insertion hole of the lower plate and the tool insertion hole of the upper plate correspond to each other, the fixing screw can be operated by inserting a tool such as a screw driver from above the dielectric resonator. Therefore, there is no need to perform work while holding the dielectric resonator as in the conventional case, and the fixing screw does not fall out, so workability is extremely good,
The burden on the operator can be reduced.

Furthermore, it does not require special parts like conventional cap screws,
Since commercially available screws can be used, there is an advantage that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a mounting structure of a dielectric resonator according to the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is an enlarged sectional view of a fixing screw mounting portion, and FIG. 4 is a sectional view of a conventional example. It is a figure. 1 ... Columnar dielectric, 2 ... Upper plate, 3 ... Lower plate, 4, 5 ...
Side plate, 7 ... Tool insertion hole, 8 ... Tool, 9 ... Screw insertion hole, 10 ... Fixing screw, 10a ... Head, 13 ... Ring, 14
…… Exterior case, 15 …… Screw hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Takagaki 2 26-10 Tenjin, Nagaokakyo City, Kyoto Prefecture Murata Manufacturing Co., Ltd. (56) References JP-A-61-61503 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. A dielectric resonator having an upper plate, a lower plate and a side plate, wherein a columnar dielectric is fixed between the upper plate and the lower plate.
In a structure for attaching to a bottom portion of an outer case having at least an upper surface opened, a tool insertion hole formed in an upper plate, a screw insertion hole formed at a position corresponding to the tool insertion hole of a lower plate, and the screw insertion hole. A fixing screw that is inserted into the hole with the head part on the upper side, and the head part is rotated by the tool that is inserted into the tool insertion hole, and an elastic pull-out that is fitted to the downward protruding part of the fixing screw part. Attachment of a dielectric resonator, comprising: a retaining ring; and a screw hole formed in a bottom portion of an outer case that supports a lower plate of the dielectric resonator and into which a protruding portion of the fixing screw is screwed. Construction.